App v3.16.1 failed to connect to server

Hi,

I’m running NC 21.0.3 and have multiple clients such as the Ubuntu one (v3.2.4) and Android v3.16.1. Web and Ubuntu client works fine but Android doesn’t.

For the last few days the Android client keep telling me “Server not available” together with refusing to access files, download or upload.
The “Uploads” folder says: “connection error” without further details
Server side, I don’t have that much details:

nginx error log: nothing related to this issue

nginx access log: HTTP 204 replies: no content
[06/Aug/2021:15:26:41 +0200] “GET /index.php/204 HTTP/2.0” 204 0 “-” “Mozilla/5.0 (Android) Nextcloud-android/3.16.1”

NC logs: nothing seemingly matching my issue
{“reqId”:“aiUIbiqlAoxxxxxxxdQq”,“level”:0,“time”:“2021-08-06T13:27:27+00:00”,“remoteAddr”:“xxxxx”,“user”:"–",“app”:“contacts”,“method”:“GET”,“url”:"/ocs/v2.php/cloud/user?format=json",“message”:"/appinfo/app.php is deprecated, use \OCP\AppFramework\Bootstrap\IBootstrap on the application class instead.",“userAgent”:“Mozilla/5.0 (Android) Nextcloud-android/3.16.1”,“version”:“21.0.3.1”}

logcat logs for Nexcloud app:
08-06 15:57:58.541 1142 1195 I ActivityManager: Start proc 21130:com.nextcloud.client/u0a336 for activelaunch {com.nextcloud.client/com.owncloud.android.ui.activity.FileDisplayActivity}
08-06 15:57:58.583 1142 1740 D ActivityManager: attachApplicationLocked() app=ProcessRecord{44db3ea 21130:com.nextcloud.client/u0a336} app.isolatedEntryPoint=null instr2=null
08-06 15:57:58.612 21130 21130 D ActivityThread: handleBindApplication()++ app=com.nextcloud.client
08-06 15:57:58.613 1142 1184 V ActivityManager: Changed top to 10336,ProcessRecord{44db3ea 21130:com.nextcloud.client/u0a336}
08-06 15:57:58.637 21130 21130 D ActivityThread: ActivityThread::handleMakeApplication() data=AppBindData{appInfo=ApplicationInfo{d80fed6 com.nextcloud.client}} appContext=android.app.ContextImpl@d15e557 appContext.mOpPackageName=com.nextcloud.client appContext.mBasePackageName=com.nextcloud.client appContext.mPackageInfo=android.app.LoadedApk@67d5844 data.restrictedBackupMode= false data.providers= [ContentProviderInfo{name=com.nextcloud.client.firebaseinitprovider className=com.google.firebase.provider.FirebaseInitProvider}, ContentProviderInfo{name=org.nextcloud.documents className=com.owncloud.android.providers.DocumentsStorageProvider}, ContentProviderInfo{name=org.nextcloud className=com.owncloud.android.providers.FileContentProvider}, ContentProviderInfo{name=com.nextcloud.android.providers.UsersAndGroupsSearchProvider className=com.owncloud.android.providers.UsersAndGroupsSearchProvider}, ContentProviderInfo{name=org.nextcloud.files className=androidx.core.content.FileProvider}, ContentProviderInfo{name=org.nextcloud.imageCache.provider className=com.owncloud.android.providers.DiskLruImageCacheFileProvider}] Caller=android.app.ActivityThread.handleBindApplication:7440 android.app.ActivityThread.access$1500:301 android.app.ActivityThread$H.handleMessage:2148 android.os.Handler.dispatchMessage:106 android.os.Looper.loop:246
08-06 15:57:58.637 21130 21130 D LoadedApk: LoadedApk::makeApplication() appContext=android.app.ContextImpl@cdb7d2d appContext.mOpPackageName=com.nextcloud.client appContext.mBasePackageName=com.nextcloud.client appContext.mPackageInfo=android.app.LoadedApk@67d5844
08-06 15:57:58.651 21130 21130 I TetheringManager: registerTetheringEventCallback:com.nextcloud.client
08-06 15:57:58.651 21130 21130 D ConnectivityManager: ConnectivityManager() mContext=android.app.ContextImpl@cdb7d2d getOpPackageName()=com.nextcloud.client getBasePackageName()=com.nextcloud.client getPackageName()=com.nextcloud.client
08-06 15:57:58.709 21130 23911 D NetworkUtils: Searching known-servers store at /data/user/0/com.nextcloud.client/files/knownServers.bks
08-06 15:57:58.751 21130 23930 D ThumbnailsCacheManager: thumbnail cache dir: /data/user/0/com.nextcloud.client/cache/thumbnailCache
08-06 15:57:58.926 795 1221 I SurfaceFlinger: id=45316 createSurf (1080x2400),1 flag=404, com.nextcloud.client/com.owncloud.android.ui.activity.FileDisplayActivity$_21130#0
08-06 15:57:58.926 1142 4707 D WindowManager: makeSurface duration=0 name=com.nextcloud.client/com.owncloud.android.ui.activity.FileDisplayActivity$_21130
08-06 15:57:58.929 1142 4707 I SurfaceControl: release : mNativeObject = 511336748496 - Surface(name=com.nextcloud.client/com.owncloud.android.ui.activity.FileDisplayActivity$_21130)/@0x3cd99fa / android.view.SurfaceControl.writeToParcel:1136 android.view.IWindowSession$Stub.onTransact:910 com.android.server.wm.Session.onTransact:143 android.os.Binder.execTransactInternal:1190
08-06 15:57:59.060 1142 1193 I Pageboost: Launch time gathered : pid 21130 com.nextcloud.client 481
08-06 15:57:59.072 795 795 D SurfaceFlinger: DEVICE | 0x7bd5f44bd0 | 0002 | RGBA_8888 | 0.0 0.0 1080.0 2400.0 | 0 0 1080 2400 | com.nextcloud.client/com.owncloud.an[…]ctivity.FileDisplayActivity$_21130#0
08-06 15:57:59.154 795 795 D SurfaceFlinger: DEVICE | 0x7bd5f44bd0 | 0002 | RGBA_8888 | 0.0 0.0 1080.0 2400.0 | 0 0 1080 2400 | com.nextcloud.client/com.owncloud.an[…]ctivity.FileDisplayActivity$_21130#0
08-06 15:57:59.233 21130 21130 D EmergencyMode: [EmergencyManager] android createPackageContext successful: com.nextcloud.client
08-06 15:57:59.236 21130 21130 V InputMethodManager: Starting input: tba=com.nextcloud.client ic=null mNaviBarColor -15592942 mIsGetNaviBarColorSuccess true , NavVisible : true , NavTrans : false
08-06 15:57:59.244 21130 21130 V InputMethodManager: Starting input: tba=com.nextcloud.client ic=null mNaviBarColor -15592942 mIsGetNaviBarColorSuccess true , NavVisible : true , NavTrans : false
08-06 15:57:59.296 21130 23908 I WM-WorkerWrapper: Worker result SUCCESS for Work [ id=df15cd12-0ddf-4a34-b787-05bad85f163a, tags={ com.nextcloud.client.jobs.MediaFoldersDetectionWork, timestamp:1628258278713, *, name:immediate_media_folder_detection } ]
08-06 15:57:59.613 21130 23912 I WM-WorkerWrapper: Worker result SUCCESS for Work [ id=0fff2726-95b9-4ecb-bed5-720cb99dfae7, tags={ name:periodic_files_sync, com.nextcloud.client.jobs.FilesSyncWork, timestamp:1628258278694, * } ]
08-06 15:58:48.552 21130 21130 V InputMethodManager: Starting input: tba=com.nextcloud.client ic=null mNaviBarColor -15592942 mIsGetNaviBarColorSuccess true , NavVisible : true , NavTrans : false
08-06 15:58:48.578 795 795 D SurfaceFlinger: DEVICE | 0x7bd5f402b0 | 0002 | RGBA_8888 | 0.0 0.0 1080.0 2400.0 | 0 0 1080 2400 | com.nextcloud.client/com.owncloud.an[…]ctivity.FileDisplayActivity$_21130#0
08-06 15:58:48.926 21130 21130 I SurfaceControl: release : mNativeObject = 511336372960 - Surface(name=com.nextcloud.client/com.owncloud.android.ui.activity.FileDisplayActivity$_21130)/@0xd0531c5 / android.view.ViewRootImpl.destroySurface:2441 android.view.ViewRootImpl.setWindowStopped:2289 android.view.WindowManagerGlobal.setStoppedState:734 android.app.Activity.performStop:8423
08-06 15:58:48.932 1142 1184 D SurfaceControl: hide : mNativeObject = 511874055664 - sc.mNativeObject = 511336675360 - Surface(name=com.nextcloud.client/com.owncloud.android.ui.activity.FileDisplayActivity$_21130)/@0x444efd3
08-06 15:58:48.932 1142 1184 D SurfaceControl: nativeSetFlags Done : Surface(name=com.nextcloud.client/com.owncloud.android.ui.activity.FileDisplayActivity$_21130)/@0x444efd3
08-06 15:58:48.939 795 1223 E BufferQueueProducer: com.nextcloud.client/com.owncloud.android.ui.activity.FileDisplayActivity$_21130#0 disconnect: not connected (req=1)
08-06 15:58:48.958 1142 1999 I WindowManager: Destroying surface Surface(name=com.nextcloud.client/com.owncloud.android.ui.activity.FileDisplayActivity$_21130)/@0x444efd3 called by com.android.server.wm.WindowStateAnimator.destroySurface:1794 com.android.server.wm.WindowStateAnimator.destroySurfaceLocked:765 com.android.server.wm.WindowState.destroySurfaceUnchecked:3911 com.android.server.wm.WindowState.destroySurface:3885 com.android.server.wm.ActivityRecord.destroySurfaces:5236 com.android.server.wm.ActivityRecord.destroySurfaces:5217 com.android.server.wm.ActivityRecord.notifyAppStopped:5276 com.android.server.wm.ActivityRecord.activityStopped:5899
08-06 15:58:48.959 1142 1999 I SurfaceControl: release : mNativeObject = 511336675360 - Surface(name=com.nextcloud.client/com.owncloud.android.ui.activity.FileDisplayActivity$_21130)/@0x444efd3 / android.view.SurfaceControl$Transaction.remove:3449 com.android.server.wm.WindowSurfaceController.destroyNotInTransaction:225 com.android.server.wm.WindowStateAnimator.destroySurface:1794 com.android.server.wm.WindowStateAnimator.destroySurfaceLocked:765
08-06 15:58:48.959 795 1223 I Layer : id=45316 removeFromCurrentState com.nextcloud.client/com.owncloud.android.ui.activity.FileDisplayActivity$_21130#0 (115)
08-06 15:58:48.963 795 1221 I SurfaceFlinger: id=45316 Removed com.nextcloud.client/com.owncloud.android.ui.activity.FileDisplayActivity$_21130#0 (115)
08-06 15:58:49.891 795 795 I Layer : id=45316[1] Destroyed com.nextcloud.client/com.owncloud.android.ui.activity.FileDisplayActivity$_21130#0
08-06 15:59:09.404 21130 23912 I WM-WorkerWrapper: Worker result SUCCESS for Work [ id=2eacccf2-86ef-4cf5-bf41-53bd6bfedfb8, tags={ com.nextcloud.client.jobs.MediaFoldersDetectionWork, *, timestamp:1610625063395, name:periodic_media_folder_detection } ]
08-06 16:04:30.482 795 1221 I SurfaceFlinger: id=45340 createSurf (1080x2400),1 flag=404, com.nextcloud.client/com.owncloud.android.ui.activity.FileDisplayActivity$_21130#0
08-06 16:04:30.483 1142 4205 D WindowManager: makeSurface duration=2 name=com.nextcloud.client/com.owncloud.android.ui.activity.FileDisplayActivity$_21130
08-06 16:04:30.487 1142 4205 I SurfaceControl: release : mNativeObject = 511336633136 - Surface(name=com.nextcloud.client/com.owncloud.android.ui.activity.FileDisplayActivity$_21130)/@0x475efc3 / android.view.SurfaceControl.writeToParcel:1136 android.view.IWindowSession$Stub.onTransact:910 com.android.server.wm.Session.onTransact:143 android.os.Binder.execTransactInternal:1195
08-06 16:04:30.637 795 795 D SurfaceFlinger: DEVICE | 0x7bd5f3d910 | 0002 | RGBA_8888 | 18.0 36.0 1062.0 2357.0 | 0 0 1080 2400 | com.nextcloud.client/com.owncloud.an[…]ctivity.FileDisplayActivity$_21130#0
08-06 16:04:30.640 21130 21130 V InputMethodManager: Starting input: tba=com.nextcloud.client ic=null mNaviBarColor -15592942 mIsGetNaviBarColorSuccess true , NavVisible : true , NavTrans : false
08-06 16:04:30.702 795 795 D SurfaceFlinger: DEVICE | 0x7bd5f3d910 | 0002 | RGBA_8888 | 6.0 13.0 1074.0 2385.0 | 0 0 1080 2400 | com.nextcloud.client/com.owncloud.an[…]ctivity.FileDisplayActivity$_21130#0
08-06 16:04:30.974 795 795 D SurfaceFlinger: DEVICE | 0x7bd5f3dc70 | 0002 | RGBA_8888 | 0.0 0.0 1080.0 2400.0 | 0 0 1080 2400 | com.nextcloud.client/com.owncloud.an[…]ctivity.FileDisplayActivity$_21130#0
08-06 16:05:12.426 1142 1722 D ConnectivityService: requestNetwork for uid/pid:10336/21130 NetworkRequest [ TRACK_DEFAULT id=5444, [ Capabilities: INTERNET&NOT_RESTRICTED&TRUSTED Uid: 10336 AdministratorUids: RequestorUid: 10336 RequestorPackageName: com.nextcloud.client] ]
08-06 16:05:19.401 21130 24939 E ReadFileRemoteOperation: at com.nextcloud.client.jobs.OfflineSyncWork.recursive(OfflineSyncWork.kt:118)

Any idea?
Thanks