Help! Is this wrong?

My husband and I were buying a home contract for deed. While living there we had to carry home owners insurance. In our contract it stated that the seller must cut down a tree that was in the front yard and we were not responsible for any damages caused by the tree untill this was done. The tree was dying and had caused damage to a neighbors home. In july of this year we ended the contract and moved. 11 days after we moved a storm came through and knocked the tree down causing extensive damage to the house. Our homeowners policy had not run out yet. We had no idea any damage had been done until yesterday when we received a check from the insurance company for almost $4000. We did not file a claim, the mortgage company did not file a claim. They just sent an adjuster out on their own because a lot of homes had been damaged that day. Can we keep the money? I have spoken with the insurance company and they know we no loger live there. The check is made out to us... contuined..