How long does a construction company have to file a lien on a customer who is almost 90 days late on paying an invoice for a job in Tennessee?

customer issued a Purchase order for an estimate, work was done and the terms was verbally agreed on for two payments the first one was progress billing and the second one was for major completion, as of yet no payment has been made, the accounts payable office stated they was having cash flow problems but did not indicate when a payment could be made.