so I am arriving in MAD T4 on Wednesday Sept 13. I know there's an ALSA bus at noon, but it leaves from Avenida America (I want to avoid a mad dash into Madrid, don't know if my flight will arrive on time at 10am or not) As for the credit card, I don't even get to the page to input the card information; I just constantly receive a "ERROR AL REGISTRAR EL PAGO" . I've tried using Google Chrome, Safari and today, Firefox. On both my laptop and desktop. No luck.
UPDATE !!
I gave it one last shot and used my iPhone. It worked. I was able to get to the page to put my payment information in and it was accepted no problem (Chase CC) Thank you everyone. Hopefully this will help someone else down the line.