My fathers land line is out of service.

On August 5th,I found out my fathers land line does not work. He is in his late 70's with no internet / computer in his home. He called customer service and after around 30 minutes was told AT&T would look into it. He has no dial tone inside the house or at the service access box outside the house. When anyone calls his landline, they get a busy signal. As of 6 pm Eastern time today, still no working phone at his house. The neighbor behind him had their driveway dug up yesterday, but no evidence of calling Miss Dig to locate wires or anything else. How can I help him?