How can I dismiss liens from subcontractors against my property?

I had an extension/renovations done to my home in Virginia. I entered a contract with a construction company before any work was done. But in the contract it was explicitly stated that the contractor was responsible for any payments to subcontractors and suppliers. I was only responsible for sending a consistent amount of money for each of the 3 specific deadlines during the construction of my home. We even ran into problems before the extension was complete; like the workers for the company of the contractor not having their own payments. Even then there were threats of liens being said against us. The contract has been paid in full along with our extension being complete. But recently we have been told by one of the subcontractors for our house, that were part of the first steps in the renovation, that they still haven’t received payment. How can I dismiss this and prevent any other liens being filed against my property?