Having trouble with my contact sensor

I ordered the ring contact sensors, i have the alexa echo 5th gen, my contact sensors are not doing anything, one of them is not working period and the other one is working but no responses from doing the factory reset. I want to know do i need the ring alarm for those contact sensors to work? My plan is to use the contact sensors by them selfs, i was watching a video smart home solver and Reed said, he uses the contact sensors as a stand alone. If anyone can tell me what i need to do i would appreciate it, thanks