Worsed Customer Service

On the 26 may 2019 ive purchased a lenovo phone from power fashion store in kuruman and i have not even used it a week and when i went back to the store on the 2nd june 2019 they said the phone should be send sway for repairs. From the first day the other sim port didn't work and it kept freezing when a memory card is inserted but it says the phone supports up to 16gb but even with a 2gb memory card the phone is slow and freezes and some apps just open then closes. I went to powee fashion store more the 3 times to ask about the phone and why cant thw exchange it but the won't and just come up with excuses and said the phone is send to their factory in durban where the send it to vodashop for repairs and till today i have not got a answer from the regarding the phone