Because the excess contribution to the traditional IRA was made in 2021 and we are long past October 15, 2022, an excess traditional IRA contribution now has to be corrected by making a distribution of exactly the amount of the excess. In 2024 TurboTax you would enter the code 1 or code 7 Form 1099-R with the IRA/SEP/SIMPLE box marked by substituting a zero in box 2a rather than entering the reported box 2a amount (which would be the same as the box 1 amount). This would cause TurboTax to prompt you to enter an explanation of a return of excess contribution after the due date of the 2021 tax return, allowing TurboTax to treat it as a nontaxable distribution.
TurboTax employee experts are more experts on the operation of TurboTax than on the IRS guidance regarding this sort of transaction error that does not directly involve TurboTax. I would guess that most CPAs are unfamiliar with this situation as well. It relies on knowing several things: that a traditional IRA is not an account eligible to receive a rollover from a Roth account, that the deposit into the traditional IRA is a failed rollover and therefore constitutes a regular contribution rather than a rollover contribution, how one goes about obtaining a distribution of the excess after the due date of the tax return, and how one might be able to complete the original rollover by self-certifying to the Roth IRA custodian that the situation would qualify for a waiver of the 60-day rollover deadline.
Note that the traditional IRA will still be subject to the RMD, which can be satisfied with a distribution of any amounts remaining in this traditional IRA (investment gains) or a distribution from another of your traditional IRAs.
