How do you get your credit limit fixed?

How do you get your credit limit increased, or fixed?



I have tried reaching out to Verizon several times, (see below), and apparently no one there knows how to do it so I'm trying to figure out how to do it on my own somehow. 




To whom it may concern,

I have been a Verizon customer for over a year now. 
I actually just decided to switch over to Verizon FiOS for my home as well. So far I have been happy with both of my choices until today.
I am beyond frustrated with the customer service and communication issues. My problem is simple, and I already spoke to a rep from the credit department two weeks ago who told me what I need to do to fix this problem. And no one I've talked to since then knows how to do it apparently.
I am trying to upgrade my phone, which I just paid off, to the new Samsung flip phone in Graphite. I owed $84.67 on an old account I forgot about, the representative told me that I just have to pay that off and then they can increase my credit limit because they put it to zero because I owed money. She said once I pay it off to call back into the credit department and they would increase my financing limit. 
I have tried chatting several times, I have called every department you can think of, and talked to about 15 people so far, and no one knows who I should talk to or how to get this resolved. I finally got through the to the credit department today, and I was told that they can't help.