The experts will chime in I’m sure but my understanding is that the event that triggered the “Wait” function, in this case the motion sensor, has to be true when the Wait period ends. My guess is that the sensor is not detecting motion when your Wait expires so the siren is never switched on.
I have learned (from this group) to call the “then” section of a separate program, which includes the Wait command, and it will run as you intend.
Hope this helps. Let me know if you would like some examples and I can post later.
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