Compressing Animations - Loading forever

Hello,

When I click on duplicate > retarget an animation, I am getting this ‘Compressing Animations’ warning. It never goes away (I left overnight and it crashed) and I can’t see why this is being trigerred.
The original animations are all saved and submitted through Perforce, and they play normally when I click on it. The warning just appears when I try to retarget it.
Using UE 4.27

Any suggestion on how to fix it is welcomed. :slight_smile: