If you used the integration before May 2020, and recently re-authorised WorkflowMax/XPM access, the sync may not be working because your portal has not yet been migrated to support the new version of the WorkflowMax/XPM API. Please contact support via https://support.hubspot.workflowmax.com and ask for your portal to be upgraded to support the new version.
After the 30 day free trial has expired, there will be a monthly charge for the integration to run. If for some reason the billing information was not filled out during setup, or the billing information has expired, the sync will no longer run. Please note this is also required to get the 30 day trial to be enabled. If you are still experiencing issues, please contact support via the portal (http://support.hubspot.workflowmax.com) for assistance.