MTN BAD SERVICE

I wanted to upgrade in November, Blackfriday special, signed a contract , but DSV couriers never delivered, and then after 2 months of phoning constantly, emailing ,emails, they promise and apologize, but nothing was done, and they cant give me the upgrade because blackfriday is passed even if i signed contract. They also cant supply me with another upgrade because they cant delete the upgrade on their system.. i had to pay near to R2000 for them to take all off and was promised they will refund me its just to fool their system.. now they can only refund me that if i pay R700 to get my own refund.. oh and they blocked all my accounts, accidentally, but cant open it because of system.. once i mentioned im taking them to newspapers and social.. all of a sudden theh unblocked my account, but they still have not cleared my account and still no refund