Can you confirm that you mean the Alexa or Smart Life application on your phone can be used to switch on and off? Note that there are two apps for Smart Life. One is obviously called Smart Life, the other is Tuya. I would recommend that you enable the skill for both and then run the device search again.
I can turn the light on/off using both the Alexa app and Smart Life. I checked the wifi as I have a dual band router. The 5G band is listed but not used for anything in my home. I will try installing the Tuya app and see what happens. Thanks for the info!
Using the Device icon, the echo in the bedroom and kitchen are both listed as well as the switch which Alexa instructions had me change to light. There isn't a change option for wifi or anything else. I did check to see what band is selected in my iphone settings and the 5G option is listed but not used for anything.
I downloaded the Tuya skill and enabled it no problem. It found the device and I can turn it on and off with both apps. The Tuya skill put another instance of my device in the list in the Alexa app. However- Alexa still can't find it.
I have a similar issue so I want to chime in on this. I have a smart plug from SmartLife and it's connected to a lamp, called 'Pink Lamp'.
I have two 2nd gen Dots, one in the kitchen and one in my daughter's bedroom. First, I added the skill SmartLife to my Alexa, no issues turning the plug on/off using SmartLife app or Alexa app. However, I could use voice command on my Dot in the kitchen but NOT in my daughters bedroom. That one just replied, can't find a device named 'Pink Lamp'. Both Dots are registered to the same account and both are using my 2.4 GHz WiFi.
Since I'm using Smartthings (but SmartLife is not compatible with ST), I decided to use IFTTT to trigger 'Pink Lamp'. So, I created a virtual switch in Smartthings, using a simple IFTTT applet that turns SmartLife 'Pink Lamp' on. Then I'm using Alexa to turn my ST virtual switch on/off. Now Alexa has no clue I'm using SmartLife (since some people on other forums blamed SmartLife and the plug) but the same problem remains! I can use voice command from the Dot in the kitchen but the one in my daughter's bedroom still can't find the device named 'Pink Lamp'. I've tried to de-register that specific Dot, same problem.