2 days running round still not unlocked

[Chriso]

Have an issue with changing SIM card to EE says not supported been o2 shop told nothing they can do customer service sends do not pick up had text through saying phone unlatched it’s not have failed security question On phone so can’t re try to unlatch Can someone help please

[Bambino · Accepted solution]

@Chriso What phone is it and when did you buy it?

All customer service numbers available are here: Guide: Coronavirus Community Help and Support 

[MI5]

@Chriso 

The answer to your security question is different from your password and can be reset in your MyO2. 
once you've done that, how to unlock here Guide: Unlocking an O2 phone to use a different SIM card