Help · about 2 mins
Replies land against the right event, and you stop double-booking.
Two things switch on. Email means a client's reply is filed against their event instead of getting lost in your inbox. Calendar means Celestial can see when you are already busy, so a date you have taken elsewhere stops being offered to somebody new.
These are run by the company in question and are the ones to trust if a screen looks different from what we describe.
At least one connection is listed against your account in Settings.
Sent back without connecting usually means you approved on a different Google account than the one you meant — check which account the consent screen named. If your workplace manages your Google account, an administrator may have to allow third-party apps before this can complete.
Coordinators. Connect the calendar you actually run your days from. If you keep a separate personal one, that is the one that causes the double-bookings.