You should leave the direct debit in place until it's paid, if you've cancelled it you need to call cs or see if you can still access your account through your MyO2.
http://www.o2.co.uk/contactushttp://www.o2.co.uk/myo2Additional help here
http://community.o2.co.uk/t5/Discussions-Feedback/Ways-to-pay-guidelines/td-p/874982
I have no affiliation whatsoever with O2 or any subsidiary companies. Comments posted are entirely of my own opinion. This is not Customer Service so we are unable to help with account specific issues.
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