Problem update

Good morning;

I am having problems with the free Salon Booking plugin.
When I update it, the whole “Appointments” section is deleted and I have already had to restore the website twice.
Also, I don’t know if it’s because it’s not updated, but now it’s showing up as booked times that are not really booked.
Thanks for your help.

Best Regards

The page I need help with: [log in to see the link]