MTN is Useless

MTN Does Not want to sort my problem out!!!! I upgraded my Contract in August 2018 and added an extra Wifi to my contract, I have been given less data on my wifi from sep2018 to Dec 2018 and MTN refused to refund me as well as my contract i sighned is R559 and is fixed and they charged me R1956 september for the wifi, i have paid my accounts every month and because of the over charging i only paid what i signed for and MTN has suspended my account they have done it for 4 months now on and off and now my fone has been suspended for a month already, i have asked MTN to lodge a call to resolve this problem and noone can help me, I dont understand my wifi is the problem and yet all my contracts with MTN have been suspended i find it unfair that i must pay for a service i cannot use due to the problem beinig with MTN...MTN is useless and i have had endless problems with them since i have upgraded... please can u contact me **********