Koodo has recently been working on their self serve site. Ive noticed its been down a few times when I have attempted to use it.
You may need to call in and ensure that everything is set up correctly, or, have a password reset done. I'm not 100% positive, but if you attempt to log in with incorrect credentials too many times, the system will lock you out, force a password reset or challenge you with one of your security questions.
Additionally, it may also not like the email address you're attempting to use? This is a long shot, but I've seen things like "email address is too long" or "please use a different email address" appear because Koodo likely prefers having reputable email services used for increased reliability in the customer receiving something important like their bill.
Not saying that's the issue, just that it could be.