Bad customer service for Faulty device sold to me

Really bad Customer service, I bought a mtn cellphone, This device was faulty and I returned it for repairs in Jan 2022. They fixed it but 3Months later the same problem occurred. In March 2022 I took it back for repairs it was repaired, In August it had the same error again and returned it again for repairs then the phone was returned to Markhams store at the Avenues in Springs and not fixed with no feedback. Today I went to Markhams at the Avenues in Springs where I bought the phone cause its almost 4 Months waiting for the repairs and no communication from them. The guy at Markham store called Mtn to ask what is happening they say no the repairs was canceled by the courier company, how is that my problem when I was told in August they will fix my phone, They giving me stories for the last 3months ,it going for 4 months now, They refusing to refund me or replace the faulty phone with a new one, This whole year i was inconvenient with no phone cause this phone is more in for repairs then in my possession for usage and the same error every time . They took my money and sold me a faulty device and mtn dont want to take responsibility for their incompetence. They are the worst I will never ever buy a phone from them ever again or recommend their products and services to any one.