Alexa stops discovering devices

Alexa can’t find any new devices I’ve added to Smartthings. I disabled/enabled Smartthings skill but there is no change.
What else can I try to get Alexa to recognize my new devices again?

In Alexa App go to, More, Add a Device, Other, Discover Devices.
Are you on iOS or Android? Maybe try the other one.

I use Discover Devices in the alexa app (android), but alexa can’t find anything. A month ago, Alexa automatically added new devices.