Worst company ever. I took out a contract and the next day I found they had better deals on pay as you go and so I cancelled well within within the cooling off period. They however decided to still migrate my mobile number and my mobile number went dead. I phoned them to find out what was going on and they admitted they messed up. They got my mobile number back on pay as you go. At the end of the month I received a bill from them for a day's line rental. I tried phoning them, but their answering system says goodbye and they cut me off. Their web chat is manned by a bunch of headless chickens who take their time responding and then keep ending the chat while I was typing replies, this was within seconds. They then could not find my account and they kept saying that I couldn't have been charged as it was a pay as you go number. I have wasted over two hours and still no where forward. I'll be contacting Ofcom. Never Ever will I use o2 again, I'm porting my number to a different network.