question

We have one customer who must dial 1+area code to reach our main number.  We have a business account with a non-ported number.  We are in the biggest suburb of Kansas City as is the customer.  They are less than a mile from our office.  They don't have to dial a 1-area code with anyone else in our area.  It's a problem because their staff perceives it as a long-distance call and they have to get prior-authorization to make long distance calls.  From what I can tell, their carrier is SBC.