Ok ... you do understand the IRS is a BIG machine and one part doesn't talk to the other in real time so it sounds like the 2020 return has not been processed yet AND you did not pay the balance due on the return because you know the change means you do not owe it which is OK. However the automated department sent the CP12 notice incorrectly and the department who is recalculating the return has not caught up to your return yet and until they do you can simply ignore the incorrect CP12 notice OR respond back stating they are premature in sending the notice. Nothing else you really can do but wait for the IRS to process the corrected return and I know this is upsetting but the IRS is coping with the situation as best as they can under the circumstances.
