CellC R99 data deal

I have been a loyal customer with Cell C for a few years now. Currently I have 20gig (5gig + 15gig) contract which I took out last year for R199 per month with no device. In 2014 it was only a 12 month contract. In 2015 it was a 24 Month contract and I am now bound till the end of January 2017. I have phoned the CellC customer help lines to negotiate a better rate with no assistance, so much for loyalty. My unhappiness comes from the fact that it is advertised all over that you can get the same deal for R99 plus a LTE device. I never use the 15gig after 12 o'clock and had to cap the 5gig from getting enormous R800 out of bundle bills. It would be more beneficial for me to take out the Telkom 5gig contract with an LTE device. It this is how CellC treats me as a loyal customer I will be C'ing you at the end of my contract and that is how you spoil a business relationship and loose a loyal customer.