you enter numbers and answer questions in Turbotax. based on those Turbotax calculates a refund or balance due. then you file. the IRS gets the return and if they find that their computer records do not match what you reported they change your return. Turbotax is not notified so if it showed a $500 refund that's what it will always show though the IRS might change it to a $5,0000 balance due. Normally you should expect a letter/notice in 2 to 4 weeks explaining the changes and how to respond if you disagree. Perhaps they got lost in the mail. By now your transcript for 2020 and maybe even 2021 should be posted so you can go to the IRS website and review your tax return transcript. it will show what you reported and what the IRS computers calculated as correct.
https://www.irs.gov/individuals/get-transcript
