Cellphone repair

I purchased a Hisense U962 201 from Ackerman's promenade on Sunday 04/08/2019. After having cellphone for just over 2 weeks I returned the cellphone as I was have endless problems with the device. On the 19/08/2019 I booked the device for repairs where I was informed it will take exactly 1 month from the time the service provider collects the device for me to get my device returned. (Service provider collects 3 days from date cellphone was booked in 22/08/2019) On Sunday the 22/09/2019 I contacted the store to find out if I could collect device and was informed that the device is still at repairs and someone will get back to me Monday 23/09/2019. On Monday 23/09/2019 I received a call from Ackerman's staff member who informed me that they will only be able to provide me with feedback by Thursday. This is unacceptable, as this was not the agreed turn around time nor did I receive any communication from Ackerman's or MTN untill today.