Owncloud App with Nextcloud 10.0.0 and iOS 5.1.1 (iPad1)

I have an iPad1 with the last iOS version (5.1.1) installed.
After upgrade from Nextcloud 9.0.53 to Nextcloud 10.0.0 the iOS Owncloud App (Version: 2013 iOS2.21) on the App does not work anymore.

I can login and can I can also refesh the content in case there are ONLY folders.
… in case the folder contains a file the following error message appears: “Connection to server is not possible”

I had no issues with the iOS App with Nextcloud 9.0.53

Do you have an idea what I can do?

Thank you in advance for your response and best regards
NC2016

-> Title updated

Can you try if you get the same problem on demo.owncloud.org (OC 9.1) and then report this to the ios-app bug tracker: https://github.com/owncloud/ios/issues