SHOCKED! UPSET! VERY DISAPPOINTED!!

In 2014, June, I took out a 5G 12month data package with Cell C. In 2015 the package expired and the same offer was introduced to me with a month to month package of R99. I continued with the data package. Then in March 2016, I discovered that there was an amount that was pending on my account stating I owe cell c hundreds of rands. I contacted the customer services on 2016-03-15. Spoke to a very helpful lady that informed me that my data package was used up and the amount charged was out of bundle rates. I was very surprised and shocked on the amount. I didnt realise how I had run my 5G package up within two weeks of a new month. I thought maybe various updates with programmed to automatically update. I went back and changed my laptop format. On 2016-05-01, I logged in and checked my data package just to discover data was being subtracted, even though I had logged in after 1am. This is where my free 3G after 12 data gets used. I contacted Melly at customer services that set the record straight stating that I no longer have the 5G package but instead have a 2G package anytime. I was never informed of this change and have now paid R600 odd on a data package that I thought was 2G anytime and 3Gfree data after 12am. I am extremely upset and angry with this service provider for its, once again, lack of informing their customers of changes on their account. I have been a loyal customer of almost 12years but think its time I make a change in networks!!!!