Yeelight Ceiling 480 not working with Alexa anymore!

My old Yeelight ceiling 480 have been working just fine. I got 2 new ones and could not connect them to Alexa like I did with the others before. They work in Yeelight App, but are not recognised by Alexa App/Services. Disconnected all - now the old lamps cannot be used with Alexa like the new ones. Fix it!