Have you called in to cancel or pause your account?
If not then you would have continued to be charged for it.

If you haven’t checked on your account since Oct 1 you’d be pushing 3 months without payment. I would log into your account to see where you’re at and make a payment before it gets sent to collections (assuming it hasn’t yet)..

To place your phone on a seasonal hold “pause”, it will still cost $15 per month.

https://www.koodomobile.com/en/help/keeping-your-account-open-when-travelling

You may want to cancel completely 

Thank you for your prompt response, yes, I want to cancel it completely.

You said you want to use that number upon your return to Canada. If you cancel it, there’s little to no guarantee that you will get that number back.

If you are okay with that and still want to cancel, since you are outside of Canada, you can reach out to Koodo via Facebook https://m.me/koodo or Twitter/X https://twitter.com/koodo and a rep can help you there with the cancellation.