I bought a 3-pack of smart dimmers. Installed two with zero problems;

The third one was installed about 8 feet away from the other. It's on the same circuit, but it is NOT a three-way switch. 

The third switch powered on and controlled the ligths via the hard switch (absolutely has the white wires attached). I got the red and green blinking wifi symbol, however, the switch did not produce a wi-fi address on any of the devices I tried to connect it with.  After multiple devices and resets of the switch (wifi and total re-sets), I contacted customer support, who determined the switch must be bad.

I got an RMA and returned the switch and they sent me a new one

I installed the new switch and had the exact same issue. I do not believe it is a switch issue. In part of my trying to figure this out, I reset the working KASA dimmer switch near the one that did not work, only to now find that in trying to re-establish the connection, that the working one also now did not produce a wifi name on any device. 

I removed the third switch and then the other one started producing and address again and was able to be reconnected.  T

Any thoughts on what exactly is going on here?