A customer messaged me saying "All payment methods for this shop are temporarily unavailable."
My payment methods are all verified. Don't know whats the issue.
Please help.
The customer is correct. You have no payment options showing. You'll have to contact Support.
eta - Your book can be found on a site owned by the author whose name is very different than your own. It uses the same cover photos, the same questions, terminology and page layouts. You might want to reconsider contacting Etsy.