Facebook Shop is a mess right now. Most features are regularly not working, product catalogs are disappearing one day and back the next, the shop edit section works depending on the hour of the day.
All that to say that I wouldn't trust the Facebook Commerce Manager right now to work properly. You can try and contact the dedicated Facebook Commerce Manager support team (they usually reply within a day), but keep in mind that the first thing they'll ask you is screenshots and then tell you to try on a different browser, or a private window to check if the problem persists. This first advice usually doesn't work, but it's worth doing—just to let them know off the bat that you've tried it (and maybe help them move faster into solving your issue).