Help with armature animation ,stretching animation in Armory 3D

[RashidApp]

Hie guys my animation is stretching ,sometimes it does not ,making me wonder whether If Im doing something wrong or its a bug
https://drive.google.com/file/d/1ITF_AVT2zpDWQY-qxKDWCoNNdoCzIEDE/view?usp=sharing