No Control over your own account usage

I just called Mr Price head office and I queried why I could not buy any airtime from them because lets face it Mr Price does not cater for the plus size people in the world they only care about skinny model types, so all they good for is home d?cor and airtime, I paid my account before the time and I paid extra, once I got denied airtime over Mr price mobile, I called head office and I got told everyone has a R300 a month limit, its a new month so the R300 should be active... wrong we customers need to wait until their month end which is the 7th of every month, so us customers must wait, but when it comes to payment then its an issue I come from a retail back round and this is poor delivery and NO customer satisfaction at all. Mr price is seriously lacking in customer service and fashion for the plus size people.