My yeelight led strip was connected to my wifi router and my mi account. My wifi router got auto reset for which I had to setup my router again. Now whenever I open Yeelight App, even though the led strip is on, it shows offline in the app (with my mi account signed in). I tried resetting the led strip. After that whenever I try to link the led strip with the app it says ‘connection timed out’ after completing 100%.
Please make sure if the lamp connected to your router, if yes, try changing DNS to 8.8.8.8.