Property Purchased is now being claimed by other person basing on prontote

Dear Sirs, good evening. I Purchased a residential property in Visakhapatnam, Andhra Pradesh in April 2016 From Mr C. Since then we have been living there with my family without any issues. Recently 2 weeks before we understood from our neighbor that our House is set for Auction by PDJ Court, Visakhapatnam. surprised and shocked we approached our Relative / Lawyer with the news paper cutting. there is a O.S number and E.P number mentioned on it. so it seems that Mr C has borrowed 20L from Mr B against 2 pro notes in 2014. we Purchase the property from Mr C in April 2016. we opted loan from ICICI bank as well, as all the documents were clear, and EC is also clear we proceeded for registration. its only now we get to know about this as we understand that court order to proceed Mr C Property which is Mine now. now with our lawyer to postpone the auction by 2 weeks,. we started to trace the whereabouts of Mr C only to understand he has deceased 4 months before. Please advise your thoughts.