Mtn bad service

I app**** for wifi. Received it after 2 weeks, but have battled to get it set up for 2 months. They just don't answer the call centre. Eventually I managed to get hold of someone via email. After a month's correspondence I found out that they set it up so that the mobile wifi only works at my delivery address, which is my work address! I told them to send a courier to fetch their wifi, I am not interested in their bad service and to not debit my account. They just debited my account. For something I cannot use. I am not amused! Bad bad service!!