I'm not sure what the problem is. If you are active military and contributing to the TSP, that should be a payroll deduction (or not if ROTH).
Unless you're contributing to an IRA (or spousal IRA) in addition to the TSP, you shouldn't have to answer any questions about IRA at all.
Perhaps I'm misunderstanding, but you must have checked a box stating you were contributing to an IRA. Review your input and make sure you're aren't answering that you contributed to an IRA.
**Disclaimer: Effort has been made to offer correct information; but due to the discussion forum limitations, the poster disclaims any legal responsibility for the accuracy of the poster's response**
