1040EZ form voucher from another state

As part of my tax return after filing, I received a 1040EZ payment voucher from a state (KY) I was stationed in as a result of my Military orders.  As I have always done I file my state taxes with my legal state (NE)of residency which is different from the state I received the irs payment voucher.  Don’t understand why I am being sent a IRS payment voucher for a tax the is not my state of legal residency and I was only in that state due to my military orders?

thanks