No Airtime

I have been trying since yesterday morning to get airtime additional to my contract. I even phoned tis morning 140 to try and load another R100 of airtime, all to no avail. Cell C confirms that the airtime has been loaded on their side, but I still can't make calls. I switched from Vodacom to Cell C a couple of months ago, major mistake. Too many areas where I can't get reception either. Lost the call to 140 whilst in Milnerton!! Even tried to solve my problem at the Hout Bay Cell C branch. Now, over an hour later, I still don't have airtime! Come on guys, shape up!