I was wrongly charged over £50 by o2. Having canceled my contract and sent my phone back due to the dreadful coverage. I was told that I wouldn't be billed, this, however, turned out to be untrue. 2 Months later and I have been constantly lied to and fobbed off regarding my refund. It's come to a point now where they claim the issue is with my bank, whom I have never had an issue with before. I have spoken to my bank and there is no record of a refund whatsoever. My advice is to avoid this company like the plague, they have the worst customer service I have ever experienced.