So did you get a letter from the IRS with a tax due? Watch out for scams. What does it say? Maybe it's for something else not the dividends.
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 them in the wrong box. Do you have an amount on line 30?
