Disgusted by Foschini's service

I bought my Samsung phone J4 on mother's day from foschini (springs mall),it started giving me problems and I sent it back to the store on 01/06/2020.They told me that the phone would baxk in 4 TO 6 weeks.Till this day the phone has not returned, no one contacted me yet.I keep on going there each week to check if the phone is back and they keep on telling me that they will call me.6 Weeks has passed long ago,its almost 3 months without a phone and yet they expect their monthly instalment paid. Can they give me the phone or cancel the bill!!!! Take care of your clients!!! This is unacceptable.