Are you referring to Samsung Pay? You can change where that shows up in the settings of the Samsung pay app. It can be on the lock screen, home screen or when the screen is off. It can be on all 3 or any combination of those.
You can swipe from the very bottom to bring up Samsung Pay (usually it defaults to your card) so you can initiate a payment quickly. It is there so if your phone is unlocked you can do it quickly but it can also be set to do it from the lock screen.