Answer:
Depending on the state and the agreement you signed when you took the loan they may have some legal recourse against you. In most cases if you have already paid the interest on the loan more than once, you have probably paid them back their money plus so they may be able to work with you.
If you are past the point of working it out you can wait unitl they send it off a collection agency and then you can wheel and deal to set it up. Most payday loan companies don't want to deal with you so you should be able to offer them a settlement and go. The only way they can get your refund is if it is decided in a court case.