No images on the directory

Hello, excuse me for English (I’m French).

All my files are in the same place:
series name


episode - (1x01) - episode title.mkv

I have about 50 directories and I don’t know why, I don’t have a picture of 5 of them.
However, I have the image on the directory of each season.

How can I do it?
Thank you in advance,

I finaly find solution, the directory must have the same name as the files.

But I have another question:
Why do some series have a “flag” “serie tv” black the vertical of the picture. How do I get all my tv shows to have this “flag”?
Thanks in advance,

The “Flag” Serie tv is a spam that a group has left on thetvdb website. Since it’s user supported it’s difficult to police all of the content that people add. If you try an “Edit Metadata” in Infuse it most likely will change that picture to a more current and correct one that doesn’t have the Serie tv flag. Also if you join thetvdb forum you can bring the pic to the moderators attention and it will be removed.