The configuration changes to the availability group listener were completed, but the TCP provider of the instance of SQL ...

The configuration changes to the availability group listener were completed, but the TCP provider of the instance of SQL Server failed to listen on the specified port [%1!s!:%2!s!]. This TCP port is already in use. Reconfigure the availability group listener, specifying an available TCP port. For information about altering an availability group listener, see the "ALTER AVAILABILITY GROUP (Transact-SQL)" topic in SQL Server Books Online.