Make sure that the specific sensor shows the expected values in the app. Also make sure that these values change when you expect them to. I’m playing Cpt. Obvious, but when sensor values won’t change, nothing will happen.
Then make sure that your flow trigger is waiting for the right device. I made a lot of ‘copy and paste’ mistakes in the past, when copying flows for another room.
FWIW, I had a similar issue when installing a presence sensor into a new room. I copied and pasted an existing flow but forgot to change the test for light level, so it was using the light level from the wrong sensor.
If you go to the Advanced Settings section of the motion sensor’s device tile, there is an option ‘Exclude from Zone Activity’. Is that set to No? So the device is allowed to trigger zone activity.
My suggestion is/was to delete the AND card and to replace the WHEN by a Message card that writes a message to the time line, so you are sure you are testing the WHEN card.
When the zone is active a blue dot is shown to the zone in the DEVICE tab.