Complaint Review: Reliant Energy

Hi,
For the month of september 2008 , I got electric bill of $88 and for the month of oct 2008 I was sent a bill of $380+ from reliant energy.

When I asked them can you please justify how its possible for an apartment with a single bedroom and the A/C almost not running more tham 20 days for the colder october month, they have no answers.

I got all my appliances inspected in the apartment from the maintanance and everything seems to be fine.
Can you please suggest me what else can I do to let the Reliant Energy hear my voice and try to correct it?

Thanks

Jk
richardson, Texas
U.S.A.