I bought the HS210 to replace both of my standard 3-way switches. Everything I read and researched online said nothing about needing 5 wires. The only "important" factor I saw was neutral was needed. Why is this not listed anywhere that you need 5 wires? 

I do have 5 wires at one of the old switch boxes, however only 4 wires at the other switch box. When I turn the light on from one of the switches, the other switch doesn't work. Also, many times I cannot use the app to switch it either. I then have to reset the switch and twice I have had to go back and reinstall the switches set-up through the app. I have had a neighbor who has been a certified electrician for 20+ years (knows nothing about smart devices) double check all of my wiring. 

Can I just use the basic wiring and have the "Travelers" be Wi-Fi? I know it might take an extra second or two since everything has to be sent out through the internet. However, I can wait a second or two and have it work properly, than constantly fighting with it to work.

Any serious help is greatly appreciated.

Thank you.