Follow the process here http://ee.co.uk/help/help-new/getting-started-and-upgrading/unlock-your-phone/unlock-a-ee-device-to-...
Welcome to the community.
I can see you have had some great advice from @Damienw1
Let us know if you need anything further 🙂
Did you buy this device yourself new direct from EE or is it 2nd-hand? The process & costs are different.
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