Customer Support and handling

HI, I joined Cell C to get better service at a reasonable cost, which is what they advertise. But to date I can only say I made the biggest mistake of my life. To date I still have no proof that they actually amended my contract to the originally requested and promised offer. I also do not get any Invoice nor Itemised billing however the debit order comes off religiously?! Could someone from Cell C actually uphold your advertised service promise and resolve this for me?