I was hired to install 2 fireplaces and provide the pipe and other materials. I completed the initial part of the work on 07/26/22. I have installed 2 fireplaces and need to finish the top part but had to wait for the siding to add the termination cap on. Customer is acting as general contractor on a new build and has made a partial payment of $3050 with an outstanding balance of $1970. The outside is finished and ready for me to complete but the customer has dropped all communication. At what point, can I file a lien? Thank you!