Service providers taking their clients for granted

I was contacted by an agent from MTN to offer me a laptop on special offer only for reliable MTN customer where I have been selected for the special promotion. I got interested as my daughter had just finished matric and she is now ready for tertiary education.After accepting the offer,the product was delivered to me and to my surprise it was a laptop that was for a early learning childhood.took it back to MTN where I was told the agent is from independent company not MTN as I was told to believe. I struggled to contact the agent company as I was given their contact info.Ultimately through MTN The Glen manager I went through and I was promised that internal investigation will be done before I can return the laptop.After I struggled to return the laptop I was told time for cancellation was over the company can not take it back or I am penalised.Prior to all this I approached MTN explained my story and I was referred to the agent company.When the billing time came MTN was now the company combining my current contract with the agent company that I struggled so much to reach for cancellation and to return the laptop. I finally handed it back to MTN and promised that all other documentation will be processed and cancelled. I did not believe when my services were blocked that I owe MTN R13000.On further inquiries I was told that I am in arrears with my cash payment which I was doing when MTN debited R13000 from my account. I reversed and pay cash at Mtn’s outlet.After discussion with billing department and promised that things will be resolved and my service restored I believe that all is well.As I am asking you for help I am told my account has been handed to MTN legal department.Why? I am in areas which I wasn’t aware that MTN is not debiting my contract of R510. Please Hello Peter help me to find out if I am wrong.For your info MTN has been loading my monthly data whereas I wasn’t paying for four to five months.