Anita, it is working perfectly for me, both within the lesson directly, and through linking externally to the YouTube site.

You might need to go through support as it is possibly regional or your local settings etc (VPN/antivirus software etc) 

Anita, 

you could try going directly to YouTube, searching Léo et Popi and Galette des Rois.  The clip should work from there as it does if I set my VPN location to France, even though the embedded clip doesn’t work in the same setting.

Otherwise there is nothing that can be done from the forum - you would need to contact support to see if they have any other workaround as it is an external clip.