Checkout Issues - Paypal & Missing Shipping Rates

A customer called me the other day to report that they couldn't checkout. They were getting "User Authenication Failed". So I began to look in to the issue.

I had not changed any passwords or settings, so I didn't understand the issue. Still don't really.

I went to my Checkout/Payment Gateway Settings and Paypal Website Payments Pro was selected. I didn't have any information entered there. I had user names and passwords for Paypal Payments Advanced (US Only), but when I tried to reselect that, it went back to the Paypal Website Payments Pro. So I went to Paypal and got my API, entered that, and tried to checkout on my site. It goes through to a checkout process, but it bypasses the customer information area that usually pops up (address, phone number, etc). At the same time it doesn't add shipping or tax to the total before sending it to the Paypay Checkout Page.

Do you know what I need to do to fix this? I tried to read up on it, but I'm at a loss.

Thanks!