Why do I have to pay state taxes

No one can see your state return.    The usual reason for owing state tax would be that you did not have enough tax withheld from your paychecks to cover your state tax liability.  Double check the amounts you entered from your income.  Pay special attention to the amounts entered from boxes 16 and 17 of your W-2's, looking for typos, extra zeros or misplace decimals.

WE need more info since we have no access to your returns.  In what state do you have your permanent residence? In what states did you earn income by having income-producing property there, working there or earning income from a taxable entity such as an S-corp or partnership based there?