I'm working on some of my photos for the first time in a while in Photoshop CC 2018 and whenever I press Command+S on my mac or try to Save from the File menu a 'Save As...' dialog window pops up. I can't figure out what the problem is. When I first open an existing PSD document, the first save works fine but each successive save brings up the Save As window and I end up having to press Replace.
I'm not sure if it could be related to the file/folder permissions; the files are stored locally on my drive in my Documents folder and I have checked that folder and its contents have default permissions. I have tried resetting preferences for Photoshop to their defaults but that didn't change anything. I also reinstalled Photoshop and cleared my preferences in the process but nothing has solved it. Any help would be greatly appreciated.