Treatment of loyal customers SUCK

In Nov we had problems with Telkom line so we had to phone them from our Cell C phone. Due to being put on hold numerous times by Telkom, last month we got a bill from Cell C of R800 (we already payed R500 of the R800) instead of the normal R269. Last week my mom (her account) phoned to arrange down payment of the additional R300 as both of us lost our jobs in Nov and there's no way we can afford to pay the entire amount in one go. They said it is fine and we have 2 months to pay (which will already be hard to do without an income). Yesterday we had an emergency and when we needed to phone someone we realised that Cell C had suspended her account. Today she phoned them and they said no, she has to pay the entire amount before they will switch the service on. Till then she'll be without a phone. So you tell me is she suppose to look for another job when she has to use that phone to make calls? How do you think it is acceptable cutting someones serves after arrangements has been made and agreements have been reached?! She is do for an upgrade but after this kind of treatment from Cell C I will make sure she switches to another service provider after almost 10 years. SIES Cell C!!!