BUG in Appointment+ after GCal sync

Hello,

I use appointment+ on a customers website and it has been working perfectly for a couple of days. Today I sync with Google Calendar, and now the booking doesn't work any more. It shows, but you cant change service or book an appointment. When you skip to the next month, then it works some times.. This is really wierd and a very important thing that needs to be fixed.

Can you help me?

I've granted access, so you can check if I did something wrong.