Bookers see a 'Oh no! We don't seem to have our usual permission...' error

If your bookers see this message when they access your booking page: 

This means has lost connection with your linked calendar, or doesn't have the correct permissions to view availability and add bookings to this linked calendar. This can happen if you've changed your calendar account password, or revoked our access through your calendar security settings. 

To resolve, you can re-authorize your connected calendar account on the Integrations page. If this is a team members calendar, ask them to login to their account and re-authorize.