how absolutely pathetic is that?! My final conversation today was with a supervisor in their Business Office (whatever that means) and while she was nice, she couldn't explain the how they could screw up something so basic. Are you dealing with their Business vs. Residential group? I've heard that's supposed to make a difference but in your case, it sounds like it doesn't matter - they can just simply afford to throw away business, must be nice, huh?
I told them I'd blog, Facebook and Tweet about this and while my ex, who works for them, is a FB friend, I'm not going to hold back - they need to hear clearly and loudly that their lack of service is costing them business.
Like you, I've been very polite as it's easier to get help when behaving nicely, I did keep commenting on how much time I'd spent on the various calls and that I wasn't going to be investing anymore time being treated like they didn't care. Apologies are sure nice, but they're a dime a dozen and they still don't get the problem fixed.
I wish you luck and wish I had a solution for you!