Read-only file system (tmp)

Hi,
I didn’t resolved the last crash of NC (during upload by android app) since I don’t know what to do. I read all posts related to /tmp but I have the feeling everything is ok in my config.

I tried nc-fixpermissions in ncp-config but I get this messages ending with “data directory not found
Done. Press any key…”

{

“reqId”: “QqW4ZJmm8Ju0ksev9sSG”,
“level”: 2,
“time”: “2020-12-29T00:16:35+00:00”,
“remoteAddr”: “”,
“user”: “–”,
“app”: “no app in context”,
“method”: “”,
“url”: “–”,
“message”: “Temporary directory /media/nc/ncdata/tmp is not present or writable”,
“userAgent”: “–”,
“version”: “19.0.4.2”
}

sudo ls -lh /media/nc/ncdata/
total 148K
drwxr-xr-x 1 www-data www-data 100 nov 17 01:00 appdata_oct5ufy87tqr
drwxr-xr-x 1 www-data www-data 26 nov 17 00:54 files_external
-rw-r–r-- 1 www-data www-data 0 nov 17 00:52 index.html
drwxr-xr-x 1 www-data www-data 90 nov 22 22:34 melanie
drwxr-xr-x 1 www-data www-data 20 nov 17 00:55 ncp
-rw-r----- 1 www-data www-data 144K nov 24 06:57 nextcloud.log
drwxr-xr-x 1 www-data www-data 0 nov 27 20:58 tmp
-rw-r–r-- 1 www-data www-data 2,9K nov 19 13:17 updater.log

sudo ls -lh /media/nc/
total 2,0G
drwxr-x--- 1 www-data www-data  210 nov 20 17:36 ncdata
-rw------- 1 root     root     2,0G nov 17 00:20 swap

sudo nano /var/www/nextcloud/config/config.php
  'datadirectory' => '/media/nc/ncdata',
  'tempdirectory' => '/media/nc/ncdata/tmp',

I use nc-automount, nc-datadir. Drive was formatted to BTFRS using config tools.
Thanks if someone could point me to the good direction.
Mel