I believe the system has corrected itself. I was experiencing the same problem earlier this morning. I checked a few minutes ago and my account is no longer expired. If your account still shows as expired, then you'll have to call Koodo customer service.
Dial *611 from your phone.
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Monday − Friday: 9 am - 9 pm
Saturday: 9 am - 7 pm
Sunday: 9 am - 7 pm