Save appointment to two Gcals simultaneously


I have set up appointments+ and it is just great. How ever I am wondering if it is possible to add a booking to two separate Gcals at the same time.

The idea is to have a cal with all bookings and a separte one to share only with the service provider for a certain service.

I have setup two cals in Gcal and have configured one in the main settings of appointments+. It works perfectly. I found the option to setup Gcal sync in the WP-User profile. So I have set this up as well and linked to other cal. The main cal gets the appointments but the second one does not.

How you would this setup work please?

Thanks, S

PS: Access is already granted.