The "At Least One Error Has Occurred" message can mean a couple of things upon signup:
Your proposed password may not meet our requirements of at least eight (8) characters in length, including an uppercase, lowercase, numerical and non-alphanumeric (such as ! or #) character.
There may already be a Wondery account in our system that was created under the email address you provided. To confirm, try sending yourself a password reset email here: https://wondery.com/plus/password-reset/
If you're still unable to sign up after confirming that the above situations do not apply to you, please contact our support team here and we'll be happy to assist you further.