Unfortunately O2 no longer have email support. I live in Thailand and being 7 hours ahead I always make sure I contact them by Tugo over wifi at 3.30 in the afternoon here. That and using snail mail are your only real choices and I certainly wouldn't trust live chat to close an account down correctly.
If you get to Rayong or Pattaya let me know and i'll let you buy me a beer/Sang Som
Enjoy your adventures
Forgot to say you can pay off the device plan through My O2 but you will need to call and give 30 days notice to cancel the airtime.
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