CELL DOESNT WANT TO PAY ME MY MONEY, "****************'

I have been using Cellc cellphone contract from 2019 and I m about to finish my 24 months contract now July 2021. In February 2021 a Cellc agent called me and offered me an additional "Sim data contract" which I accepted , then towards the end of the same month of February I lost that sim card. Immediately I called Cellc to report that I lost the sim card and I would like to be helped with sim swap, then the cellc agent who was helping that time advised me that its unnecessary to do a sim swipe but rather she will cancel the lost sim card and send me a new one which I received after few days. Around end of May when I was going through my cellc statements I realized that something is wrong, that i have been getting charged two times and i couldn't understand why , only to find out that the data sim card that i lost in February and reported was never cancelled and I have paying for it for almost 5 months and not even getting the benefits. I reported it immediately again and Cell-c told me that the agent who was helping me never cancelled it, she only deactivated. Now i requested a refund and Cellc doesn't want to pay me but rather they are trying all their best to put the blame on me. I m really angry and disappointed for this ******* that is happening to me .