Assuming that this occurred in 2023, be prepared with the 1099-R, the 5498 hopefully showing the date of deposit, and the cover letter to the IRS coming approximately 16 months after April 2024 in order to respond to the IRS' CP2000. The IRS gets the 1099-R showing the distribution with Code 7.

The IRS cannot match the 5498.

THEY WILL tell you tax is due. TAXPAYER MUST PROVE that the rollover was completed within 60 days of the distribution.