Editing animations in ue4

I’m just trying to make a simple casting animation in ue4. Not sure if the program is extremely buggy or if I’m just doing it wrong. When I add key frames it works fine at first…but then when I get further along adding key frames resets the position of the bone I’m trying to animate…and it does this throughout the animation, undoing all the key frames so far…Really frustrating…Any tips?