Koodo sends an email to the address you provided at sign-up with a link to complete the account creation process. If instead, you chose to try and set up an account independent of that email, then there are two instances of an account, and thus the error message you received. At this point, you only option is to contact Koodo and have them delete the most recent account, s you can respond to the email.
Easiest way to contact Koodo is by Private Message to their Facebook Account or a DM via Twitter. Or you can call, but would have to wait for a CSR, which can sometimes take a while.