Occasionally when I send a text shortly after I get a message saying it couldn't be send, so I tap try again and the recipient then receives it 3 times, sometimes up to 6 times! This drives my friends mad and I have no idea what causes it, O2 say it's not them... anyone else get the same? This happens a lot when I'm at my desk at work, but rarely from anywhere else, which makes me think it IS an O2 issue.