The Santander app lets you unblock a card instantly in most cases.
You might have accidentally toggled the "Freeze" switch in your mobile banking settings. How to Unblock via the Santander Mobile App how do i unblock my santander debit card
By following these simple steps, Emily was able to quickly and easily unblock her Santander debit card and get back to her daily routine. The Santander app lets you unblock a card
Using your card abroad without notifying the bank (though this is less common with modern banking). how do i unblock my santander debit card