I agree with both above. I would have client double check the stimulus amounts deposited (although they seem to jive re: the cents of both). Could be the IRS is wrong (which is where I'd bet). I have had one too and in this case it was client who was off. 

As far as @BobKamman advice, I would look at difference and see if its EVEN worth going after. I had a single mom whose was adjusted and she waited 14'ish weeks and it was less than a $100. She said "Oh, hell no!!".....depends on client.