Let me clarify.
If you did not receive a stimulus payment, and did not claim a rebate, the IRS will not automatically add the rebate and you must file an amended return if you are eligible for a rebate.
However, if you received a payment (round 1 or 2 or both) and did not report it on your tax return, and so claimed an extra rebate, you don't have to amend. The IRS will fix your return for you and issue the correct refund.
Since the customer states they received a "144_B", this appears to be the second category.
