Ssa 1099 shows amount deducted for medicare, I am reimbursed for that from previous employer. Where do I remove it

[ToddL]

Are you itemizing deductions?

If, not, you don't need to do anything.

If you are itemizing, you can enter a (negative expense) in the Medical Expenses interview in Deductions and Credits. As you go through the interview, you will come to a screens for health insurance costs. The amount from the SSA 1099 will be there already. Just add a new, negative entry for health insurance costs to offset the Medicare Part B premium. 

(If that doesn't work you may have to delete your SSA 1099 and re-enter it without the Medical Part B amount. See: How do I delete forms in TurboTax Online?)