- Edit one of the Meeting Types or create a new one.
- Check Show Phone Number field checkbox.
The phone number field will show up on the booking page where the invitees will have to type in their phone number. The dial-in code is detected automatically based on invitees' browser settings.
Note that if you use adblocking software in the browser, the dial-in code won't be detected and always fall back to US (+1) country code.