Can someone help me with this Roblox studio animation bug that doesn't allow me to rotate or move?

I am trying to animate my custom R15 character, however, when i rotate or move the upper torso, it moves the lower torso in a weird way. There is an error coming from the animation plugin that says:

RotationPoint is not a valid member of Model "JointDisplay"

I was wondering if somebody could help me?

Here's the video of whats happening: https://www.youtube.com/watch?v=BfiDar-kRqs

When rigging a model, there has to be a primary part that is anchored, motor6Ds that are attached from the root part. If the parts that are not the primary part are anchored, it will not move or rotate in the animation editor. Make sure your parts are not anchored except the primary part.