Faulty Samsung device from MTN

I took out a cellphone contract with MTN,it consisted of 2 Samsung A30s phones,1 of the phones speakers was faulty a day after unboxing it. I then called in to the Mall of the South branch in Johannesburg where Ive done the contract since it was less than 5 days in my possession,I was asked to return the phone to the store to have it accessed by a technician,this was June 2020.Since then I have still not received a new handset replacing the faulty one,which I was advised will be the case once the repair center assesses the phone and gives the approval to replace the phone with a new device.The store has advised me on numerous occasions that they have called the repair center to enquire about the progress of the assessment with no avail. They have even shown me proof,the issue was even reported to the Area and Regional managers ,who advised the branch that this will be dealt with at senior level,and still nothing,I have already paid for two months for a handset that I haven't even made use of and do not have in my possession,how the hell does MTN provide a service which cannot even be rated as a service,this is the reason why I have always only made use of Vodacom and Telkom Mobile ,I only went through with this contract as I was referred by my brother,this was the biggest mistake,I would never refer anyone to MTN.