I could be that the BofA credit card isn't enabled for Online access properly.
If you have any accounts working correctly, make note of the FI association for that/those accounts.
Open the one that isn't behaving property & Deactivate them, then re-establish Online Access for those accounts, using the same FI as the account that is working.
When you sync, it should find the problematic accounts & guide you through associating them with existing Q accounts.