Money goes of each month for a cellphone i dont have disgrace from MTN

I Gertrude Visagie , purchased 2 cellphones on my Foshini acc store in Randfontein. The phone gave me problems which I had to send back withing 7 days , which I did. The cellphone was sent for assessment 16 June 2022 , i still have not recieved my cellphone. I am still paying a cellphone that I do not have. I qm very frustrated and dissapointed with this useless service from MTN they are useless , i want to open a *****ulant case against them as my money is being deducted each month for something I dont have. This is a zero reccomendation. I am going to make sure that MTN gets a bad review everywhere I go.