Good Afternoon @JamieJames.
Thanks for coming to the community, I hope you're having a lovely time in America.
What phone are you using?
Did you text ROAMING to 150 before leaving the UK?
If not, you can activate your roaming by logging in to your My EE account and following these steps:
Menu > Manage Device > Ensure both Roaming and Calling Abroad are active.
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