Hi @Lt. Columbo
Thank you for sharing the details over message.
As both the user and location is Included and not Excluded, it is expected that the sign in from UK is being blocked due to policy configuration of 'Block International'.
In the WhatIf test, 'Block International' policy is applied because the location is Included and does not apply 'Block Intntl Except UK' because UK is excluded.
If multiple policies are in scope then most restrictive policy is enforced. For details please review Assigning policies to groups and users
To fix this, you can choose to exclude the user from 'Block International' policy, re-evaluate the Named location configuration or update the Grant controls.
I hope this helps in resolving the issue.
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