Sybill may not join your external calls for two reasons:
The external invitee has an email from a public email provider (aka domain) such as gmail.com and your preference is set to ignore these public domains as external domains.
You can fix this by toggling this setting under your Settings > Profile > Internal Domains & Guests section. After you set your preference to consider invitees with public domains as internal users , Sybill will start joining these meetings.
You may have declined or responded 'No' to the email invite.
If this doesn’t work, please contact Sybill support:
Email: help@sybill.ai
Support portal: Click on the blue Intercom chat button at the bottom right of the Sybill page.
A more extensive guide on personalizing the recording behavior can be found here.