MTN Gamer+ and spam sms's

I recieved the following sms's: Y'ello. You have been successfully registered with MTN Gamer+. Your account username is *** and your password is 535110.

and

Y'ello. Thank you for subscribing to MTN Gamer+ at R3.03/day or a lesser amount. 1st day is Free. Visit now http://bit.ly/2CYEXbK. To cancel dial *155#. Call 135 for help. Ts&Cs www.mtn.co.za.

Firstly, i did not register for this. I did not authorize this.

Who gave you permission to register me for these charge services and to send me so much marketing sms's?

I did not sign up for Gamer+, now i must waste my time trying to disable it myself. Please dont reply and say i am not longer registered for gamer+, thats because i took the sim card out of my router, put it in a cellphone and cancelled the service.

I then phoned 135, and am being told i clicked on some pop up on my computer, really??? The sim is in a router, what pop up am i clicking exactly??? Incredibly frustrating. Do you see the issue, it is that you automatically register me for services and try to charge me but the sim card being in a router, i never find out. I then asked the agent to chat to a manager, instead i get left hanging on the phone.

If this is how mtn does business and supports its client's, i will happily cancel this contract. MTN really does have the worst service of all networks.