Phone still not received back

I took my Huawei handset as it stopped working and was under warranty in at The Pep Cell Store in Guguletu Mall. I took it in three weeks ago and was told to collect it after two weeks, I went to the store and they kept telling me its on its way. I then went yesterday to check it and its been 3 weeks now still the handset was not at the store. the service was pathetic and I am without a handset . I need it urgently as I ran out of patience , I have been told different stories and still no phone