Wholesaling Seller wanting to back out

I have a signed purchase and sale agreement between me and a seller and they now want to back out. The contract was signed 2 weeks ago. Last week they were wanting to back out then said they wanted to go through with the sale. Now they are saying they want to back out. I have a contract and have spent a ton of time on this. I even have a buyer lined up. I want to avoid legal fights if possible. Would love to hear some thoughts.