vodacom contract

I recently took a 24 months contract (upgrade ,a Sumsung galaxy A51) on June 2020. The customer service agent told that the phone will come with R175 aitime and 20G data at R299 per month. I took a contract coz I was a great deal,to my suprise on 1 August when they were suppose to load the monthly allocation nothing was loaded. I then called customer service beside her attitude she told me: 1. The airtime was loaded and depleted on the 1st for data, off which I did not convert my airtime into a data. 2. The 20G that was promised is now a once off allocation i won't getting any data I have asked to speak to a supervisor but the urgent said I must lodge a complaint with her .I asked for call recording of the day I took the contract,till to date I haven't received any positive response from Vodam. I'm very disappointed and feel that I have been mislead into entering in this contract. I tried to also cancel the contract with no luck. Kindly assist