It could be an issue with your folders:
The Title of the game is based on the TitleID found in the path and the corresponding Title in GameTDB.
for example, if you put Luigi mansion in :
games/Luigi's mansion [GLMP01]/game.iso, then all is fine.
If you put Mario in
games/Mario [GLMP01]/game.iso, then Mario will have Luigi's mansion GameID, and the loader will use Luigi's mansion files for that game (Name, covers, etc.)
Verify that your folders hare the correct Title ID for the corresponding game.
You displayed always the same "channel"?
You clicked on the one at the bottom, It has Kirby banner and paper Mario picture?
or it's two different channels?
one picture shows "developer: unknown" and the other one "developer: game's sub title".
So, I guess it's two different channel, or you closed/reopened the same one?
Maybe your ISO is corrupted/bad too.
You can delete the cached file for that banner. Like Terro said, go to game settings>delete menu>delete banner cache.
You don't need to redownload the banner, the loader will re-generate the banner from the game iso.
if you select to download banners, it will replace the banners to the one he created.
You can also disable the cache (it will read the game ISO every time), but it's slower to load.