HS210 3 way switch does not detect if light is on
I got two HS210 3 way switches, one works fine but another always shows that the light is off even if it's on. This is both in the app and on the switch itself (the lit up circle). When using the HS210 switch to turn the light on it shows that the light is on for a second or so (in both the app and the lit up circle on the switch turns off) and then the app changes status and shows that the light is off and the circle lights up again as if the light is off, even though the light stays on. I've tried this on 2 different lights with same result. The wiring is correct, I've got it connected to white/neutral, black/load and then 2 travellers and I can switch the light on/off with the smart switch or with the dumb switch on the other end of the 3 way. Do I have a dud?