Both the numbers 020 0222 0700 and 0900 still work as does the 0800 0565265.
Some suppliers dont allow access to both of them,but usually one works
Try this service
http://www.0800buster.co.uk/ instead.
Dial 0333 555 8800, then enter the full free-phone number , then press #
03 numbers are treated the same as 01/02 numbers.
Or if you have smartfone you can use this app.
http://www.wizardapps.co.uk/0800wizardOut of interest what mobile network are you calling from ?