Hello Emanuel,
You are correct on both points.
acknowledging the event does turn off repeat notify for the alarm on that event. Also when an error/warning/critical event is generated its is kept until it gets resolved or the condition persists. So there won't be multiple events( with different eventIDs) generating on the same object for the same instance of the object state.
This behavior is common for all the events.
Now in your case, if its not, this needs some debugging.
Can you paste the event details here.
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