Pre paid 365 days Data

In December 2017 I went into the Cell C store to purchase the data that lasts for 365 days - I am on a Top Up contract. I did this in 2016 and managed my data for 2017 so well that we had data every month. When I got to the store I asked the sales person when am I due for an upgrade as I seriosly need a new ph as my existing phone's battery is not good any more, the sales person said in January 2018 I said ooh great I will come in then and upgrade. In the meantime I would like to purchase the 365 days data as this works out so much cheaper for me - seeing that I am on a very tight budget and this in turn then ensures my child could get access to google for school projects. The sales person and myself then actually went on to look at the fact the the 200GB is an even better deal than the 100GB data that I purchased the previous year. I then said okay let me buy the 200GB data at R1999.99 which to me is A LOT OF MONEY but in the long run it means we are sorted for data for the whole of 2018 and it does work out cheaper. Yesterday I went into the store to go and do my upgrade - not the same sales person this guy then went on to tell me that I will loose my data I was SHOCKED!!! I said to him but NO ONE said anything like this to me when I purchased the data in December even though they looked up on the system when I was due for an upgrade!! I DO NOT have money to through around and if I was told this I would have waited to first upgrade and then purchase my yearly data. I am HORRIFIED at this so I said to the sales guys so now Cell C is forcing me not to upgrade or if I upgrade I loose all this data! He even ph customer care and they confirmed I would loose the data!! I went home feeling sick!! I ph custome care myself - thinking this cannot be true and little did I know what this gentleman was going to add to this story (as in the back of my head I'm thinking okay worst case scenario I must just hope that my ph will last another year untill my data is finished at the end of 2018 and then I will upgrade) no says the customer care guy your data will expire wether you upgrade or not as the contract comes to an end on the 21st of April - he suggested that I get the new handset as I will loose the data in anycase!!! I CANNOT AFFORD to buy more data this was hard earned money for a single income widowed person - this is WRONG CELL C - WRONG and I am NOT going to leave this here you cannot do this!!!!