It can take upto 24 hours, it all depends how many are going through the system at this moment in time. You could call CS to check if it is showing as pending on your account.
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.
Please select the post that helped you best and mark as the solution. This helps other members in resolving their issues faster. Thank you.