Appalling Customer Service!!!!!

In 2014 I purchased a Cell C Data USB for R600 - including 3GB (valid for 365 days) and have subsequently always purchased the same R299.99-3GB bundle ever since - 3GB will usually last me a minimum of 1 month and up to 3 months using it for Skye(up to 2 hr calls once or twice a week) and Internet Browsing.<br> On 10 Jan 2016 I bought 3GB at Cell C Cresta - on 11 Jan 16 I was only able to make two brief 30min calls before my data was depleted - OBVIOUSLY CAUSE FOR CONCERN! Never happened before!<br> on 12 Jan I went in to complain, first they customer service agent called said they would only review the matter at month end, i refused to accept this - they then said they could do the validation in 24-48 hrs. THEY NEVER CALLED and only sent a useless sms. I had to purchase another 3GB due to delay and the data again was depleted - which is abnormal!<br> I've been into the Cresta branch at least 4 times as well as called to complain and be refunded. Mandisa does not know how to ensure customer service complaints are solved or rectified and this whole matter is seriously aggravating and unprofessional. <br> Cell C should contact me and refund me. I am a paying client and I deserve RESPECT & SERVICE!