I am having weird HomeKit automation issues; I can't tell if it's a HomeKit problem or a Kasa device problem.

I have two Logitech Circle View Doorbell Cameras, and two Kasa (TP-Link) light switches.  The doorbell cameras are at my front door and my garage door; the light switches control the front porch light (where the first doorbell lives) and the outside garage light (where the other doorbell lives).  Both cameras sense motion (and record) as expected, day or night, independently of each other; when either camera senses motion, I get the appropriate motion-/person-/animal-detected notifications sent to my phone in a very timely manner.  Both light switches behave as desired and expected to control their respective lights; i.e., one press of the switch turns the light on, another single press turns the light off.  Normal.  Neither device is set to be "Group with Other Accessories" within HomeKit.  

Now, I've created HomeKit automations for each light switch: "When Motion Detected in [Front Door|Garage], Turn On; only at night; turn off after 15 minutes."

Problem 1: Whenever "night" falls (I think that seems to be the trigger), both lights turn on.  No motion sensing is required for this to happen (I get ZERO notifications that any motion was detected, as I do normally), they just turn on for no good apparent reason whatsoever.

Problem 2: Despite the rule saying "turn off after 15 minutes", neither light will turn off after the specified time; once it's triggered to turn on, it will never automatically turn off.

Problem 3: When I try to manually turn the lights OFF (both behave this exact same way) they will turn back ON almost immediately, within a second; a second attempt to turn the lights OFF will actually turn them OFF and they remain OFF.  For a while, anyway; at some point (like 15-20 minutes?) it will turn back ON, AGAIN with NO notification of any motion detected.

Anyone seen this? Anyone know what this is happening?  Most importantly, how do I make it behave the way it should?  (Disabling any time constraints—I did change "at night" to specific hours, as well as removed it completely, all to no avail—on the automations will "fix" the problem, but then I'm turning on lights unnecessarily with every motion, day or night.)