I filled in payment details online the other day - I knew the card number, start date and expiry date and security number. I had to sit and think when it came to filling in my name, my mind went blank.
yes, that is curious. I quite happily remember and type 12 & 16 digit numbers but I always get my debit card out and 'ready' for that 3 digit security code. lol. Must be a psychological thing.