It will blocked it as its not from a UK IP address and depending on the location will be geo-blocked due to a financial fraud risk.
I am afraid you will need to call in to do this.
Current Phone: Sony XPeria Pro-I and Motorola Razr 5G I also have a Planet Computers Gemini
I work in IT as an Enterprise Messaging and Collaboration Tools Administrator (Office 365, Slack and much much more) and manage hardware both Mobile and Desktop / laptop, my desk is a bit like PC World
-- We are all customers and dont have access to any o2 accounts