Why video ads are not shown in YouTube videos that are posted on our sites via youtube api? On the YouTube website, video ads are shown

Why video ads are not shown in YouTube videos that are posted on our sites via youtube api? On the YouTube website, video ads are shown.

Are there video ads on YouTube? https://youtu.be/rFXWg_1X9VAThere is no video and advertising on the site? https://app.expert-music.com/youtube-freemium/c/0Video on the site through YouTube ApiHelp me understand why video ads are not showing?