How to create an alert for when learners join the waitlist for an offering?

Summary:

I need to create an alert to go out to learners that have joined the waitlist of an offering and also another alert to go out when they official get off the waitlist and are part of the class. I have read the other threads on customer connect on this topic and have tried the filters but it is not working. Has anyone created these alerts before? Any help would be greatly appreciated!

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