We can only advise you what to do (it is why you asked here in the first place) but ultimately the choice is yours.
o2 won't replace until they have had 3 attempts to repair the same fault and quite often we hear stories of them reporting the fault was water damage or some such other made up story......
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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