Received a message from Santander saying that "suspicious activity" has been detected on your account and they need you to click on a link on the message to prevent a "lockout"?

DELETE IT. It's a scam

Remember:

• A genuine text message from your bank will never ask you to provide passwords, personal or financial informations in a message.
• Your bank will never ask you to click or download a link.
• Your bank will never use language such as "you must act."
• Never share a Santander One Time Passcode (OTP) with another person. Not even a Santander employee.
•  Never download software or let anyone log on to your computer or other devices remotely following or during a cold call.
•  Never enter your Online Banking details after clicking on a link in an email or text message.