Expected filesize mismatch - one file repeatedly creates an error

Nextcloud version : 21.0.1
Operating system and version: CentOS Stream
Apache or nginx version: Apache/2.4.37
PHP version: 7.4

I am getting an error popup every time I am changing files on my client that 3 files could not by synced due to an error and I should consult the logfile.

The Logfile is here: Pastebin link
The topmost error is here:

"Expected filesize of 1828950 bytes but read (from Nextcloud client) and wrote (to Nextcloud storage) 65536 bytes. Could either be a network problem on the sending side or a problem writing to the storage on the server side.

The error always comes for the same file, other files are fine.
I do not know where this file is actually still present on a client so I can delete it. I have looked but cannot find it.
I have restarted the server but this did not change anything.
Other files work fine.

Anyone has an idea how to resolve this?