This particular error indicates we're unable to sync some of your data because at least one of the selected contacts in HubSpot has been merged into another contact in Salesforce.
To be more specific, when you are reviewing a HubSpot contact and locate the Salesforce Sync section on the left-hand side, you'll see an error message that your contact was deleted and there will be a button provided to Undelete.
To fix this, follow the instructions below:
- Navigate to Account Menu > Integrations.
- Click on Settings under your Salesforce Integration.
- Scroll down to Delete in HubSpot when deleted in Salesforce, select the check-boxes, save your changes, and run the sync again.