This error may occur when the Target constituent and Source constituent share an Address. On the Source record, the address is marked as primary while on the Target record the address is not marked as the primary address. To resolve this error, we will navigate to the record the address is not marked as primary and update this address to be marked as the primary. After completing the merge, we can then change the primary address to an alternate address if necessary.
  1. From the affected constituent record, Navigate to the Contact Tab
  2. Select the arrows to the left of the address that is shared with the merged record
  3. Mark this address as the primary address
  4. Save
  5. Attempt to merge the constituents records again