MTN False adverti*****t

I received a call from a sales person from MTN offering 120GB of data for an amount I cannot remember, I declined the offer, the sales agent tried sweetening the deal and offered 60GB anytime data for R199, an offer I couldn't refuse because I get that amount of data with telkom for about R550. Once my sim was activated on the 22nd June I received a small amount of data thinking that because its half the month I'm probably receiving half the data - Come the 01/07/2020 I expected the new data to kick in - It didn't, Which in turn caused me to contact the call center on 06/07/2020, explained the scenario to the agent and was told to contact the call center again the next day between business hours to get in touch with retentions to cancel the contract. done that. retentions told me I would need to pay a cancellations fee unless I provided proof that I was **** to. they then transferred me to a team that'd be able to track my call I received and cancel my contract without the cancellations fee. I got through to them after about 20 minutes, I explained the whole scenario again for the 3rd time this morning and the agent dropped the line. I wasn't even angry or anything, calm and collect. I just need them to give me what was promised or cancel my contract, It's unfair, please assist.