body: I created a contract between myself and a client. The contract states that I will provide service A to the client. I provided service A. A third party is blocking the use of the end product of service A to be used for my client. My client no longer returns my emails or texts and has failed to respond to my invoices (sent certified mail and with return receipt).
  
  
  
title: Is my client free from obligation to pay an unpaid invoice under contract?