Shocking service

Dropped off a Samsung S7 phone at Samsung service centre in Constantia at the end of August and was told it will ready on the 12 September which I did receive a message that it was ready to be collected. I was there on Friday the 22 September at 9am to collect it to be told that it was sent through to Boksburg and that they haven't even started the repair and that it isn't their problem and I mustn't make it his problem. I was given the managers Cell number But that was fruitless as he doesn't even answer your call. So what should I do now ?