I personally never used a paypal card to pay for FFXI. It could have something to do with the card security they implimented awhile back.
In regards to the not being able to update your content id's, there are a few reasons this could be. At the end/beginning of every month their payment and transfer services are unavailable. Also, your content ID's are connected with your payment options/status. If you've received an error or your account was temporarly closed
due to non-payment, normally they will cancel out the content ID's.
I would suggest calling the SE's Customer Service Support and you can get advice straight from the source. They can explain everything in depth to you. (Their customer service has gotten
MUCH better over the years.)
http://www.square-enix.com/na/global.html
Once you choose the region, you should be able to locate the Customer Service/Support/Help area.
Good luck ^^