Payment Issues On Android
If it appears nothing happens when you enter your card details, it could be your Android device is blocking the payment pop up from your bank.
Pop ups are blocked by default on google chrome, this is because they can often be unwanted ads or spam.
You should see the 3D Secure box which pops up to check that it's really you making the purchase using a one time passcode or OTP. Normally it will be a text or email code or done via your banking app. If the page seems to go blank after you enter your card details then this is being blocked from opening.
Using google chrome, in the address bar at the top, click where it says pop up blocked, it might be an icon with a little x, click the link you want to see, click always allow pop ups for this site.
You could also try a different web browser or a different device or you could always pay by PayPal instead.