Choosing mtn was the biggest mistake ever

I have been an mtn customer for the past 14 years and have been on contract for 12 years until I cancelled my contract in March 2019 because one of your consultants upgraded my number without my consent. On the 3rd of July 2019 I decided to go to an Mtn store at Kolonnade to get a new phone on contract, it was approved with the expectation that I will be able to use my phone immediately, to my surprise I can only receive calls and sms on a smart phone NO INTERNET ACCESS. I called the customer care and was given the reference number 1 – *** and I was told to buy data to activate my internet access, I bought data 200MB but still I’m unable to use it. It’s been 3 days calling MTN for assistance without any luck. I am so frustrated with MTN and will never recommend anyone hence I cancelled the contract before. Can anyone assist me?