Military retirement is not a distribution from an IRA. Do not mark the IRA/SEP/SIMPLE box in TurboTax Form 1099-R between Box 7 and Box 8.
Please feel free to post any additional details or questions in the comment section.
Did you receive a 1099-R in your name? Did you receive all the distributions reported in Box 1?
Are you concerned about the checkbox for IRA/SEP/SIMPLE?