Crash when I load animation sequence from pak file at runtime on IOS

I try to load some resource from pak file at runtime on IOS.when pak file does not contain AnimationSqequnece.it can be loaded successfully.but,if has any animationsequence assets,the app will crash.I saw log file,It crashed while executing LoadClass(). and my unrealengine version is 4.24.
Can anyone help me?