Getting out of a sale contract

[Ehab Tadrous]

I am selling this property which was purchased at a tax lien sheriff sale, I signed a contract with one of those contractor guys who buys for cash, but he is not licensed and is just trying to sell it or wholesale it on the MLS, leaving me without any word on the process, The contract said they should have started the process of the Title search and notified me within a 5 business days and notify me within 20 days of any problems with the search, they did not start the search until 15 days from signing the agreement, then i sent an official cancelation he is accusing me of breaching the agreement and want to file a lien on the property for his right to buy?? is that possible to be filled?? please advise