No I had not ever purchased it before so I know it couldn’t have been. Costs like $5 I think
You know what? I just read our thread back and realize you mentioned earlier that you hadn't used the App Store version. Sorry to have asked that again.
Just to be sure, those files are stored in the Stardew Valley folder inside a folder with your farm name and the long number, yes?
There's a couple things you can try. One is to create a test farm without fiddling with many of the options. Save it, exit and quit the game after the first night to see if shows up next time in your loadable farms. That will help narrow down whether it might be a problem with your specific first farm file.
The other thing you can try is to delete and reinstall the game. Doing that will delete your SDV folder though, so you'll want to copy your farm save folder (not the whole Stardew Valley folder) to another location temporarily, such as iCloud or another Files location. Then uninstall SDV, reinstall it, and copy back that farm save folder.
Fingers crossed.