mtn's ****

I have been trying to return a device that I got on Sartuday,that I am not happy about and they have been sending me from pillar to post regarding how I should return it and why I should return it, and yet they said I have 7 days to return the device if there is something that i do not like, but apparently its not like that anymore , the s/p is trying to force me to keep something that i do not like and they expect me to pay for the device anyway for 24 months, now if that is not daylight roberry , i do not know what to call it , please help me to get the s/p to take back their device and cancel my contract ,cause this cannot be on , after so many years i have been using their contracts and being a loyal client to them, more thatn 5 years of me being a client to them , now they want to treat me as if im a person who has no rights or say in anything that involves my money, no ways.