Ok ... your military pay may not be taxed to PA however any other job would be as a non resident. If you only have the military pay then in the MY INFO section indicate your SLR is where you earned the income and do NOT mention PA at all ... that is how you keep the program from "suggesting" the PA return. Remember soldier it is only a suggestion based off your entries in the MY INFO tab and not a direct order... in the future just refuse to complete the state interview or file that state's return.
To correct this error you will need to amend all those state returns and switch to a non resident filer and indicate that NONE of the income belongs to PA to get back any taxes you have paid in error.
How to Amend
https://ttlc.intuit.com/community/amending/help/how-to-amend-change-or-correct-a-return-you-already-...