CRM sync issues are almost always one of two things: stale tokens or missing field mappings.
1. Re-authenticate the integration
From Integrations → CRM, click Re-authenticate. CRM tokens occasionally expire, especially after admin password changes on the CRM side.
2. Check the field mapping
If the integration is connected but fields are missing, open Field Mapping and verify each ConnectLoop field is mapped to a real CRM property. New CRM custom fields don't map automatically.