Credit agreement and security key

I got my handset when it was still virgin and the 2 emails that I would have received I have no longer got and I need to know my credit agreement and security code to access how much I still have to go! I phoned last week and was on the phone for 40 mins and got no where . Was supposed to be called back 2 days later and received no phone call. I bet if I just cancel my direct debit you will be on my case immediately. Is this what I have to do to get this information. You have merged with o2 but trying to get this information is impossible could some please help me