Every time I send the link to my wife for Premium Duo and she verifies our address, she gets an error. The error she continually gets is attached. When we click the link for help it sends her to a 404 page. We've tried to set it up numerous times, with the same result.
You should fill out the contact form, and someone from Spotify will be happy to help you within 24 hrs.
If you get an automated email directing you to the community or help pages, you need to reply directly to that email (even if its from no-reply) and one of the customer services agents will get back to you.