Not happy at all with Cell C service

I was always on a contract, but change to top up (buying my own Airtime and data) I am a pensioner I bought both and ask the call centre to help to load the data and airtime on my phone. Okay the lady done it but when I got my SMS it say that data is only valid for 7 days I call then again I did not want that because I needed it for be on there for the whole month Is only for when I really do need it. The lady ask me did the other I spoke to not ask me what option I need. No nothing at all I thought they will new just load the data ext. I told her this is not fair what now? She check everything and then said there is no data left on my phone I never even use my data it I am the whole time since phoning you people to get everything sorted out. The lady told me, they first the need to listen to the 1st call that I am telling the truth and will come back to me. Well I am still waiting and got no data. There service are not good at all. I cannot afford to loose money but they do not care. It was 2x R25 vouchers for data R50 id for me a lot of money I am only getting Sassa funds