Hisence Cell phone Model F31

Bought my phone from CelluCity Somerset Mall Somerset West early this year . The on off button stopped working so I took the phone back for repair under warranty on Monday 11th Dec and was told normal turn around was 10 working days. Yesterday I phoned to ask what progress has been made and was told that CelluCity took it on the 11th to their pickup point but, as of yesterday Hisence had not picked it up to take it to their repair center. That Hisence are not answering their phone or emails and that CelluCity can not give me a completion date as they have no idea when it will be collected for repair. I find this unacceptable and I am looking for an explanation and a completion date