I found this issue Forcing connection to router
However, following the instructions (delete the device and re-pair it) did not work.
I have a motion sensor in the bathroom that always falls off the network.
I thought it was battery related and got new batteries, nope
Bought a plug to use are an extended/router, nope
Keeps showing on decent as red battery, changed battery again, nope
Bought a newer motion sensor with programmable timeout, this one also still shows red battery and wont connect to the plug.
Correct. I mentioned that I followed your steps in the post referenced and have already done that. Same thing. I’ve actually repaired it 4-5 times now. No dice.