Yeelight RGB LED Ceiling Light Dimmable not working

Hi,

just bought this lamp:

But unable to get it light. Wires on ceiling are checked, old lamp is working while connected, but Yeelight is not. At the same time when I connected Yeelight to wall socket - it started to work, so seems lamp itself is not damaged.
I ran out of ideas what can be wrong if Yeelight is attached to ceiling, anyone met similar issue?

BR,
igor