Android App syncing issue

Hi, im facing an issue regarding the syncronize option. I am syncing a folder from the server to my Mobile. This is working for years wirhout any problems, but since this week, all files are downloaded from the server, not only the new ones? In the App the old files are marked with a green arrow, after hitting the sync button all files are marked with the blue circle-arrows and the download from all files starts. Any idea why all files are downloaded, not onöy the new ones?

Many thanks

I have the same issue. Nextcloud is 28.0.3 (I believe it was already the same with 28.0.2). Android app is 3.28.0; with 3.27.0 it’s the same.
There is nothing in the logs indicating an error. Sync, which used to be minutes, takes an hour now. Makes the sync effectively unusable, especially, since the sync tends to throw errors when the device goes into powersave.

I made a new post with more information and a more detailed subject, so it is more visible when someone has the same issue: Android app 3.28.0 downloading everything on sync again and again