Landlord sold the house and refuse to return the deposit

Please I need some advice here since our rental agreement is about to expire. We took a house on rent, it seems like the owner borrowed so much money and sold our house in a distress sale. The person who bought the house which we rented now, is asking for security deposit to write a new rental agreement. When we tried contacting the previous owner, he refuses to pick our call and doesn’t respond to our messages. He simply ignores every message. He doesn’t even tell if he would return the money or not. Our rental agreement expires this month and we held off the rent for this month to the new owner. What are our options here?