It's a well known scam.
Block the number and do not follow any links.
Forward the scam text to 7726 - It's free.
Other ways to report here including Action Fraud website
How to block a number:
Please edit your post to remove the link.
Follow the same advice please.
To remove the link to the scam website, in your post go to Options, then the first drop down is Edit Reply. You can then delete the link.
To forward the scam text to O2:
How to forward on iPhone: https://www.lifewire.com/forward-a-text-message-on-iphone-1999154
How to forward on Android: https://www.androidauthority.com/how-to-forward-a-text-message-870759/
Track usage, upgrade and get support with the My O2 appDownload My O2