Macos_Nextcloud app sync keeps crashing

Hello there,

I have always used Nextcloud by web app, but then I started editing folders in a separated folder. Now I wanted to sync everything so I am using the nextcloud app for MacOs (latest version) to uploaded the new files and overwrite the new file versions without having to check folder by folder what is new.

The problem is that Nextcloud synced an 80% of the folders, and now it stopped working. As soon as I run the app, after 20 seconds it crashes and stops working - giving on some files “Network error: 99”

If you need any error logs, please let me know and guide me through how to get them.

Hope you can help me because I really need to sync these missing data (about 1GB)

thanks in advance!
N.