You can check a breakdown of every bill in your MyO2
http://www.o2.co.uk/myo2There are some numbers that aren't included in your allowances for calling and texting so you may be adding to your bill each month by going outside or over your allowances.
If you can't see anything obvious give customer services a call on 202 for help.
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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