If you have entered all of your card details correctly you may see a screen pop-up saying 'Verify by Visa'.
This is an additional security check with your card provider. At this point you're talking directly to your card provider and it will ask for a password which you must have previously setup.
(Note: This is a password between you and your card provider and has nothing to do with SOS).
If you have never set up a password the system may not let you complete your purchase but this depends on individual card providers policy. SOS is not in control of this decision and you must visit your card provider's website and set up your password.
Sorry, but this will mean you may have to go through the purchasing process in our shop again.