Problem saving shared files

I have a shared folder with a friend of mine, and i synced it with a local folder on my computer, and every time i edit one file of the folder, when i try to save it on the local folder, that will be synced with the cloud folder, it gives me an error, and doesn’t allow me to do it. Only if a save it elsewhere and then move it over the original file. That way it works, so it can’t be due to permissions on the folder…
What can it be?
Thanks a lot.


Is it possible that this hasn’t happened to anyone?