TRLcam Remote Motion Sensor goes to "sleep."

[FarmerDan]

I recently bought and installed a TRLcam motion sensor for my Nikon D800 trail cam. When first deployed it seem to work fine and I had over 100 photos (3 per trigger) over about 36 hours from woodrats to coyotes, foxes, skunks and raccoons Since then, when I check the system and wave my hand in front of the sensor, nothing happens for up to 30 or more seconds, then it starts responding and triggers the camera. I have charged a battery for the sensor and replaced the one in use every time I check the camera (1-3 days). Today, I checked, it was asleep, and with no animal-triggered photos out of a total of 4 photos (1 per trigger) taken over the last 3 days. I have it set to the 3rd least sensitive PIR detection since the site is in front of cliff with only about 12 ft from camera to cliff. I've also tried setting sensitivity to the 2nd most sensitive setting. I have a Spartan Lumen trail cam right beside it set at normal sensitivity. It had 49 photos, most of skunks and red foxes. I replaced a Camtraptions sensor with the TRLcam sensor because the Camtraptions sensor would go to sleep and take about 5-10 seconds to activate, missing critical photos taken with the Spartan Lumen. I was led to believe the TRLcam sensor was always ready to fire. Is that not correct? Does anyone know why mine is not responding immediately?