• Wrong code, please check the code that we sent to your email - the digits entered do not match the latest code. Each resend creates a new code and invalidates the previous one, so they should use the most recent email.
• Code expired, please note that you have 5 minutes to verify the code before it expires. - more than 5 minutes passed; click the resend link to get a fresh code.
• We had an error sending the code to your email - the resend failed to send; check the Email Log for a Failed entry against that address, and that the New Email Verification Code Sent email is switched on.
• Invalid code - the field was left empty.

As an admin you can also disable the step entirely with Disable Email Validation Security under Business: Email.