Hi, Rachel. Sorry you’re experiencing this.
Thanks for the thorough explanation and screenshots.
There’s a confirmed issue where the Attendee Report does not update instantly for some users. It’s been hours since you created this Help Desk ticket. Do you see any sales in there by now?
Does increasing the event’s capacity cause them to appear again or does it say Sold Out no matter what you try?
FYI: we always recommend restorable database and file backups as well as performing modifications first on a staging site before modifying anything on your live/production site.