Door Open Animation in Matinee Help

I’m having some difficulty with Matinee. I’m still very new to Unreal and just learned how to make a door open. I know I did it right. I followed both the unreal docs and some tutorials, so I know I didn’t miss anything. But when I animate the door, the “hinge”, aka the edge of the door where the pivot point is, it comes off the doorframe mid-animation. It makes an arc instead of a rotation. It’s fine at the beginning and the end of the animation, but scews in the middle.

I’m a former animation student, and typically when an animation goes awry, you just adjust the keyframe in between it. But you can’t seem to do that in matinee. Anyone know why this happens or how to fix it?