When will be my tablet be looked at.

I had purchased an ACER tablet at MITABYTE Springfield and still under warranty I gave it in on the 6th March 2015 because it was not reading the SIM card. However, on phoning MITABYTE today 23/03/2015 they say that ACER has not looked at it as yet. This is ridiculous as this has passed the 14 day waiting period. I use the tablet for work purposes and this delay causes me further delays. When will this be resolved and if it cannot be resolved timeously issue me a loan unit.