Bill high for month eventhough I was not home

I was out the country from 22 Dec 2014 to 16 January 2015 and my billing period is from 15 December 2014 to 19 January 2015.<br> <br> I switched off all appliances except for the fridge and freezer yet I still got a bill of R600. Surely this is incorrect and should be corrected.<br> <br> Kind regards