This is a new requirement of the second Payment Services Directive (PSD2), which aims to add extra layers of security to electronic payments. It will require banks to perform additional checks when consumers make payments to confirm their identity. To do this, banks may ask for a combination of two forms of identification at checkout. Examples include something they know (e.g., a password), something they have (e.g., a mobile phone) or something they are (e.g, a fingerprint)
Read more about PSD2 and SCA - what you need to know