Misinformed about an upgrade! Could not make calls!

I had a 50gb contract with Vodacom. I usee the same number for my daily use, for calling and for data. A lady called in August advising I'm due for an upgrade and there's a promo for 100gb for an amount less than what I'm paying. I specifically asked whether I will be able to make calls as well as I use this number for work, to which she confirmed I will be able to make calls. Come 1st September I was upgraded to 100gb but my outgoing calls was not working. I could not make calls out. I contacted Vodacom customer care the next day and advise them I could not make calls, the agent advised it was due to the upgrade as it was a data only contract. I told them that the upgrade person misinformed me I will be able to make calls. Agent said they will escalate and will take 48 to 72 hours. I waited 3 days and still couldn't make calls and no feedback provided. I called again spoke to a different agent just to find out nothing was done, I was upset as it was affecting my work. I expressed my disappointment to their poor service and told them to escalate. I had to contact Vodacom 6 times over 2 weeks for the issue to be resolved. The 3rd agent said they'll reverse my contract to previous one. The 4th agent said reversal was done but will only take place 1st October! Again I was misinformed and was furious as I could not wait a month to make calls. I told them cancel every contract with immediate affect, to which they said I must speak to cancelation department, I hung up. I repeated my situation to 6 different agent until the last agent advised that he will place a request for outgoing calls to be enabled which will take up to 48 hours. If it was that simple, why couldn't they do this in the first place? After 2 weeks of constant calls to Vodacom, my issue was resolved. I was highly inconvenienced and now reverted to the old contract from 1st October. Absolutely terrible service!