If all information is correct and you have answered all corresponding questions regarding Form 1099-R, one suggestion would be to delete it altogether and add it back again.
To delete a Form from your return, please follow the instructions on the links below
How to Delete a Form on TurboTax Online
How to Delete a Form on TurboTax Desktop
** If you are using TurboTax Online, try switching to a different web browser first before you do this. If you are using the Phone/Tablet app, try switching to a laptop or computer, or switch to a web browser within your phone.
