What expression should I use in the alert composer so that the message trigger is on the day of the

Summary:

Could someone please help me?

What expression should I use to ensure that all notification date triggers execute today?
Currently, the system searches for the event date that is going to happen. In other words, if I add a pending collaborator today (09/28) for a start date of (10/01), the notification will only appear on the start date of the admission, but I need the notification to be sent today (09/28).
The same is happening for retroactive dates. If I make a movement today (09/28) to a past date (09/15), the message is not being sent.

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