Video not playing

I use Slideshow CK on different sites for years. I have an issue now that the videos stopped working. The Iframe is loaded, but doesn't play automatically and after click there is an error. I checked it on 4 different Joomlas. Please help.

Hi
this is a problem related to your video
if you are in https, check that the url of your video is also using https

CEd

I checked on many videos and Joomlas, the problem still occures.

One of these Joomlas is in HTTPS, the video is from YT - always in HTTPS.

Do you want a link to the site? Can I send it privately?

give me the url of your video so that I can check

OK, I managed to find out, that the link should be put in this way and not in this way I think earlier both ways worked.
Anyway, I resolved my problem, thanks for your hints.