SPS, Inc. Select Portfolio Servicing, Inc. Harassment Salt Lake City Utah

I don't get this! I gave my property back in a Bankruptcy in 2007. I have had nothing to do with the property since then. BofA had it, told me in 2012 it was FINALLY going to forclosure sale. Then they sold the loan to SPS. I told them I no longer have the property, haven't for 6 yr now, and they send me letters telling me that I still have a legal obligation to pay the mortgage (even though they have verified the BK). They send me paperwork telling me that I am in danger of losing this house, there is no current insurance info on it, etc...I left a message with them telling them that I have an atty and they can contact him and do not call me. I got yet another call and I repeated the same thing. Since that call, I have received 5 letters (1 certified) and 5 phone calls...I do NOT get it. I lost the dang property 6 yrs ago, I tell them I have an atty, gave his name and location (they can look it up), and told them not to call me. Totally disregarded all of it. What the heck am I missing?? Any one have any ideas? Thanks.