It's a well known scam.
Block the number and do not follow any links.
Report the text here https://www.o2.co.uk/help/safety-and-security/phishing-and-smishing-advice
@DanY Report the scam text to 7726, block the number and any other numbers that arrive with a similar text. Here's how to block a number if you don't know how to do it:
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