We finished the work in February. In April, due to the pandemic, we gave the customer additional 60 day extended terms. We missed the deadline for notice to owner because we didnt have the service. I started the process, and the contractor is questioning if I have the rights to file a claim if the CO is issued. Can I still legally file a lien if we have not been paid. Invoice was issued 2/12. Original Due date of invoice 3/12. On 4/8 they asked for more time to pay. We agreed, does that restart the clock?