Indexed videos not showing entire thumbnail

Hi!

I’ve indexed some Youtube videos on my side but they are not showing the entire thumbnail and it looks terrible. What should I do?

You can find this problem in here https://engramapsicologia.es/contenido-destacado/, where the videos are added using the following shortcode:

[embedyt] https://www.youtube.com/embed?listType=playlist&list=UUmNHJ9BBH8rr1ozltkU28RA&layout=gallery%5B/embedyt%5D

You can also find this problem inside the tabs widget in tabs “Presentación” and “Video Resumen”. I’ve either tried to index the videos using media library and the following shortcodes:

[embedyt] https://youtu.be/U3t3KI2FreA [/embedyt]

[embedyt] https://youtu.be/GkH6pBdy5RM [/embedyt]

Neither work.

Thanks for your help.

The page I need help with: [log in to see the link]