Imported clip display only 12frames of the 30 seconds of the clip

Hello I am really confused about this one.

First I have to say that at the begining evrything was working fine. 

I have a composition with multiple 4k clips of different lenght an evrything was fine.

But at some point i noticed that one of the clip wasn't playing right.

In checking the clip i notice that it was reduced to 12 frames both in the project and in the timeline (instead of the 30s clip in 25p (750 frames).

If i try to re-import the file into AE it display the same wrong number of frames (12).

the problematic clip and one working as intended

When i try to play the clip in VLC or windows player it work fine and display the whole 30 seconds.

More strange behaviours, i have tried to export a new version of the clip using media encoder and the new clip lenght is right (30 seconds) but display only a single image wich I imagine is the same as the 12 frames that i had in AE..

And I also tried to put the clip in premiere to link it to AE but the same behaviours as using media encoder happens. (aka 30 seconds clip but displaying only 1 image, still supposedly the same 12 frames.. audio works fine tho)

I have no idea why this is happening, as it was working fine at first.

Helllp please 🙂

PS: the framerates in the composition and clip are the same, and all the others clips are working as intended..