Checklist:
1. Token expired? Go to Settings → Integrations → GoHighLevel and click Reconnect. GHL tokens expire periodically.
2. Wrong sub-account? If you have multiple GHL locations, check that Senly is attached to the right one.
3. Permissions? Senly needs at least "Contacts: read/write" and "Opportunities: read/write". Check this in GHL under your integrations.
4. Sync log? View Settings → Integrations → GHL → Sync log for the latest error messages.
Still no resolution? Send the sync-log output to support — we will take a look.