We have been getting calls from double glazing,gas, electric companys over the last couple of weeks at all times of the day and night ,some of which just put the phone down when you have answered it .i found this company that can stop them phoning you and thought i would post it in case anyony else gets the same problem
http://www.mpsonline.org.uk/mpsr/
they also can do your address to stop unwanted mail etc