I received the same phone call I don't owe nothing. They are trying to collect from 1970 that is long gone. I told them quit calling you are nothing but a scammer and I hung up. They won't get a dime out of me that's for sure idiots.
The statute of limitations protects you, if they file a lawsuit against you. You MUST show for your scheduled court dates but your defense which should be made in your response to their court summons is the debt has expired under your state's statute of limitations. They will lose the case and no judgment will be enter against you.
It may be in your interest to consult with an attorney regarding how to word a proper defense and to file a counter claim against PRA for violations of the FDCPA. If you do everything correctly, YOU should be receiving money from them. Your court and attorney costs will also be paid by PRA.