Additive animation problem

hello
i have an additive animation of firing a gun , the animation if used on a body mesh but its not working or im not able to get to work , i searched a bit about it and tried alot but im not able to get it to work , i thought of trying another engine to check if its a problem with the animation but it works fine and dandy (the engine being unity)

trying it on unreal tho just messes up the mesh entirely , it scales massively and the mesh becomes unrecognizable , the animation itself is kinda weird but i only want the deltas to apply it to the mesh

i tried local space and mesh space in the additive tab but both dont work
also tried apply additive in blueprints but same result

any kind of help will be appreciated

please tell me