First of all were you having the fees deducted from your refund? Then after the fees is the difference about 2400? Do you have 2400 on 1040 line 30?
A common adjustment is if you claimed the Recovery rebate credit on 1040 line 30 when you already got the Stimulus payment or got the second one after you filed or reported the wrong amounts or entered the wrong amounts in the 2 boxes. If you entered the total you got for both rounds in the same box it would think you didn't get the other one.
