I have a GIF file that works perfectly fine, but when I open it in Photoshop, it stops animating and all layers change to 1 static image:
As you can see the Layers section, they all changed!
I didn't even save or export or anything, the moment I open the file in Photoshop, all layers changes! And the funny thing is, I have 116 other GIFs that don't have this problem, it's just this one file!
Photoshop version: Adobe Photoshop CC 2015.0.0