Hello @amico , sad to hear that.
No, according to the doc the alert should be only disabled if any of these conditions are met at any point in time (would be worth checking the state of dataset associated to the visual at the specific time you get the email saying that the alert was disabled):
To investigate why an alert failed, check that you still have access to the dashboard. Also check that you have permissions to the correct dataset and to the correct rows and columns in the dataset. If you have lost access or permissions, contact the dashboard owner. If you have the necessary access and permissions, you might need to edit your alert to avoid future alert failures.
Is this visual associated with a SPICE dataset configured for auto-refresh? If so, can you check on the dataset refresh history if the refresh time matches the time you received the email for the disabled alert notification?
Thanks.