Make a ball move inside a hollow ball

So I have a big hollow sphere and I want a ball that rolls along the inside of the wall evenly so it is not affected by gravity. Basically I want the ball to stick to the inside of the sphere and roll around up and down and to follow players without it getting stuck. So far I have made it so that I cant walk on the spheres walls but i dont know how to make a object do that. All I need it to do is to stick to the inside of the sphere and follow players whether they be upside down or not.

Basically all I need is a ball that can roll on walls whether it be upside down or sideways and for the ball to not be effected by gravity. So if you push it it will forever move in the direction you push it but as it is in a sphere it will move along the inside of the sphere in a loop until someone touches it and moves it in a different direction.

I cant get the ball to roll around on the inside of the sphere gravity pulls it down or it just floats about.

I have tried no gravity but then it just floats about. I have tried following players but I cant get that to work.

Could you have a VectorForce that pushes it in the direction on the closest wall, after you remove gravity?

Something like force = (rollingBall.Position - outsideSphereCenter).Unit * 196.2

And update that every physics frame.