Schemers who sell you something in the name of gifts

I was schemed by this company. One of their agent called to offer me a voucher on February and she claimed they are giving to me for free. I asked the agent if my Jet account is not going to be billed but was reassured that it will not be billed if I do not use the second voucher. She also mentioned that I will receive an SMS with the login details of which I received on the 18th of March but my account was billed on the 1st of March. I then contacted them and spoke to Phathiswa Lunda who logged the call for them to investigate. The investigation took forever. I kept on sending emails to them until Minerva responded and said I did take the contract and she provided the recording for me to listen to but she kept on saying I took the contract. I asked why my account billed before I receive the login details since on the call I was told I will only be billed if I take the second voucher. I never attempted to open the sms or redeem the voucher yet my account is billed. Why am I not getting a response of who accessed the voucher and where it is redeemed? Why have they told me that it is free since I have been a loyal customer to Jet. I am not happy with the service and Mahomed who have no surname said my account will not be refunded. How can I take a contract I know nothing about. The company is full of schemers who scheme against people