I have the V1 remote sensor that you put somewhere away from the camera to have it trigger the camera to start recording.
My solution. At least it worked for me. Like many, after I change the CR2450 button battery in my motion sensor, it would not connect. Said “offline”. No blinky lights after pushing the reset button. It was DEAD. I’m an IT guy and some equipment we use requires a special procedure to reset it. Here’s my solution.
While near my camera the I added a new sensor as if it was new. The camera said it was waiting to connect, Then I “held the reset down”, then inserted the new battery while holding the reset button down. Keep holding until it flashes. This brought mine back to life.
Key is hold the reset down before-during-after installing battery and wait for the light to blink.
This worked for me, so I hope it works for you.