If you bought it from o2 it should be available in myo2 .
But what is the issue with activation lock ?
If you forget your Apple ID or otherwise get locked out of your iphone, the activation lock if enabled, prevents access to anything after the phone lock screen. Even if the phone is factory wiped. It is unhackable to all intents and purposes, all you can do is break the phone up for parts.
Only Apple or someone with the correct Apple ID and credentials can disable it and it's why if you are selling or buying a previously used IPhine you have to make sure the activation lock is disabled. https://support.apple.com/en-gb/HT201365
@CLB- It should be on myo2
@Anonymous I do know how it works had every apple since the iPhone 3