I can't sync files issues on Windows since using Obsidian

I have not been able to synchronize files with Dropbox since yesterday. Previously I had synchronized files with Obsidian and an internal plugin. Then it suddenly stopped working. When I upload files manually, it keeps saying that it skips 19 of them. I don't know how to upload these 19 more files. They are no different than any other files. I can't empty the recycle bin. There is no button for it and there is no button to select all the files in it at once. I don't understand how a company that has been around for so long can make such stupid design decisions. I then installed the Windows app and am also overwhelmed here. I activated automatic synchronization and included the desired folder on the PC. Dropbox app says it's synced, but I can't find the synced folder anywhere. Neither online in the browser, nor on the Dropbox folder on the PC.

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