Incorrect product sold

I wanted a contract at MTN and I were advised to take the home internet router on a month to month basis. After 3 months having the month to month router I can apply for a contract with a device. MTN advised me wrong because I phoned several times and a year later they tell me that there consultants gave me incorrect information, it must be a contact sim and not month to month home internet router. I have phoned logged complaints even send a email to CEO of MTN and still no reply. It is very unprofessional. I want a devise without further delay as they advised me a year ago, I am not going to tolerate incompetence and unprofessional behaviour from MTN