Unlocking phone after pay monthly has ended

[Danielleeve7]

I’ve recently moved from o2 to sky so my mobile number has transferred. But I would like to unlock my old o2 device. How can I do this? As my o2 says I have no products and can not do it on there now 

[jonsie · Accepted solution]

If the phone is less than three years old it should be unlocked

If not, then how to unlock here

Guide: Unlocking an O2 phone to use a different SIM card