Update - 9/2/2025 @ 5:20pm
Instructure has shared that they found the issue causing notification emails to not be sent. The root cause was traced to a recent code change where a method returned a Hash instead of False, incorrectly filtering out recipients of notifications.
Instructure has pushed an update late at night on 9/1/2025 to resolve the issue. Future Canvas notification emails should be sent and delivered as expected. Thank you for your patience as this issue was investigated and resolved.