@SwagDad,
Unfortunately, the MS100 is one of our oldest devices from Kasa and is no longer supported by the platform. Previously, it was required that the MS100 be connected to the SR20, a smart router that brought Zigbee compatibility to your home.
We recommend that you return the device to the seller you purchased it from on Amazon, as we no longer provide support for the device.
Also, when purchasing from Amazon, it is always recommended to look at who the seller of the device is, as official and up-to-date devices will be listed as being sold by TP-Link or Amazon.
If you are looking to go down the route of separate motion sensors for automations, you may take a look at Tapo's Sub-GHz devices that were only just recently released to the US.