not worth the time calling the IRS.... they are just going to tell you to clear it up on your 2020 tax return.
Look at the Federal Review section and enter the stimulus that you did receive. Then look at Line 30 of the 1040 form and the Recovery Credit (the missing money) will be displayed there. That will have the effect of increasing your refund or decreasing what you owe.
I would wait to file until the end of January.. The IRS will stop sending payments on the 15th and by the end of the month any checks in the mail would have arrived.
