Unlock iPhone to use with other provider

[IPhonelock]

Hi,

I have iPhone 8 which is locked with O2 Sim. Now, when I put request from My account - Unlock device I got response from O2 referral team that provided IMEI is already unlatched.

Does that mean I can use this handset in any other country with their local telecom provider?

Thanks 

[Bambino]

@IPhonelock If the phone is unlocked you can use any sim from any provider in any country. 

[IPhonelock]

@Bambino As per O2 referral team

I'm sorry, we have not been able to unlatch your device at this time.
The reason given is:

The IMEI provided is already unlatched.

What does that mean? 

[Bambino · Accepted solution]

@IPhonelock Unlatched is the same as unlocked. Try a sim from another UK provider from a friend's phone to test it before you travel.

Edit: If for any reason you find that the phone is locked, see this guide: Unlocking an O2 phone to use a different SIM card. - o2uk