Try phoning the retentions department on 0800 0529403 mon-fri during office hours.
You may have to hold for a while(40 mins in my case)but its a free call.
As a customer who is out of contract they may offer you a good deal,although it may be subject to signing up for another twelve months.
I spoke to them when they fell out with sky pointing out there were better deals to be had elswhere.The result was
For £33.45 per month with no new contract.