Delete the 1099-R you entered and re-enter.
Answer the RMD question that "None of this distribution was a RMD" or "RMD not required" depending on the TurboTax version - because it was NOT a RMD, there were no 2020 RMD's.
If this is an inherited IRA then answer the "Is this IRA inherited" with NO. The purpose of that question is to PREVENT rolling an inherited IRA over, but is allowed for 2020 only.
Then you will get the screen to say it was "moved" and all rolled over.
Also check the box that this was NOT a COVID related distributions - it was a RMD that was returned.
That will put the 1099-R box 1 amount on the 1040 form line 4a with the word ROLLOVER next to it.
The RMD that you repaid is considered as a rollover to the same account and is not taxed.
Enter your form 1099-R normally. After entering your form 1099-R, click Continue until you reach the screen Did [name] repay any of this distribution?. Check the radio button which corresponds to your situation then click Continue and follow the interview. Enter the amount repaid as a rollover and it will be excluded from taxation.
You will still have the credit for taxes withheld shown on your form 1099-R.
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