bluemoonbaz was woken up this morning with a message for a giffgaff password reset link
I would speculate it is the member who tried to impersonate your membername, in recent days.
Whenever a genuine password reset request is requested, you are asked to choose between email and mobile number to receive it, so the mischievous member is purposely directing to your mobile number.
Without that time limited, restricted reset link, the password change page, cannot be accessed using the auto generated genine reset link. As you are the sole recipient, sit tight and ignore the link. Hopefully the mischievous member will disappear permanently.