I can not validate my card! The support say that the problem is to run on Android, I open the youtube embed on the native android browser and the video is playing.
Message from support:
Test your experience across all Twitter clients, including Twitter’s iPhone and Android apps, as well as twitter.com and mobile.twitter.com. Cards that do not work in all Twitter clients listed will not be approved. Your card loads on desktop and iOS, but not on Android. Testing instructions are available here: https://dev.twitter.com/cards/types/player#Testing_your_Card
I did not understand what I should test on android … if the card is not validated as’ll try the twitter app in android?