Can't login to adobe stock contributor.

I would like to close my account. I have some old photos on it and I got an email asking me to fill out a W-8 tax form. I no longer want to use the account. I've never actually used it. I put them on when it was called fotolia. Now I can't log in. I get the error "Authentication failed based on the information you entered." How do I resolve this issue and close my Contribution account?

Please help.