Image thumbnail not displayed

Hello,
The thumbnail of the photo of one of my thread does not appear :)

Does anyone know where this is coming from?
Is there a way to fix it, while the post is already published?

Thanks for your answers
(Actually, I find it a bit frustrating ;)

anniekins

Link please

Auntie

anniekins 2024-5-7 11:31
Link please

Thank you so much for correcting ;)
And sorry for not providing the link