Help! Posing Skeletal Mesh Rotation Not Working!

I am having a problem, what is going on is that i created a fps pair of arms and hands for my game in blender and imported it into unreal engine with the rig and everything fine. But when i double click on the arms in the content browser tab to change the position, the rotation doesn’t work. I can move the limbs and resize in it but when i try to rotate the fingers and arm nothing happens.
Please help!

Does your rig have ik bones?