Client creates conflict files instead of uploading updated versions


I am having a serious problem with Client 9.0.4 on Windows 10 (22H2, December patches) and Seafile Server CE 10.0.1 on Rocky Linux. I set it up fine and they seemed to run OK, I successfully uploaded and even synced a XAMPP folder to the server a couple of times. But today when I started the client, instead of uploading the updated versions of the files in the XAMPP folder it started downloading the files (first it downloaded a list) from the server and marking the duplicate ones with (SFConflict …). Let me tell you, it seriously messed up my whole local server environment and it will cost me some time to fix! Actually I think it first gave me a popup saying that it deleted some files and asked me some question (whether I want to continue or smth), I pressed Cancel. So can someone tell me what went wrong?
EDIT: Also, I have another server synced with this client, and previously this Xampp folder was synced with it, but I think I unsynced it as the client was not allowing me to have it synced with two servers.
Thank you very much. Regards