Unable to fix Faulty smartphone

I am writing on behalf of my Mom, who recently upgraded her contract with a brand new Samsung smartphone, which has been faulty after two weeks. She has returned 2-3 times already and upon return the problem persists. Vodacom technicians initially suggested that the microphone was faulty but did not repair it on any of the occasions. Sometimes when she phones someone she can’t hear anything and only after restrating the phone it works. I am no expert, but that is not how a brand new phone should function.

I demand that Vodacom replaces the phone as this is surely a factory default that the technical guys cannot fix/pick up.

Please contact her on ********** 220 (that is if she can hear you or you can hear her), or myself on ********** 907.