Mondo Mobile & MTN - Additional charges not agreed upon.

In January 2018 I was contacted by Mondo Mobile for an upgrade on my MNT contract. After some questions on various options I was offered a MTN My Choice +M bundle deal for R469.00 per month. (The operator's name was Nana.) It turns out that this deal is actually around R600.00... But, I have been charged R959.84 monthly which includes a R201,75 "promo fee". I have queried this at MTN Brooklyn on 10 April 2018 and was assisted by a really helpful and friendly consultant, Elsie. She told me that the "promo fee" is for a handset - which I never asked for nor ever got. This was a mistake and will be reported. No problem... I received a ref. number on 11 April: 1- ********** 1816 On 12 April it states that the query has been resolved with above ref. no. On 13 April a sms states that the query has been escalated with Ref. No. 1- ********** 4232 On 20 April a sms stated that the query had been resolved for Ref. No: 1- ********** 4232 All good? No! My June bill still reflected exactly the same issue with R201.75 "promo fee." I returned to MTN service center at Brooklyn to query and resolve this. The friendly staff looked at my profile and this time around I was told to sign the contract first before the issue can be taken further. I refused as this would be a contract I never agreed on and would appreciate that we cancel all contracts, wort out the refund and start with a clean slate. I did receive an sms with ref no: 1- ********** 7616 which said my query had been escalated. Needless to say, I am still at square one paying for a handset which doesn't exists and stuck in a contract which hasn't been signed.