Wouldn't decreasing the radius that an object revolves around, increase its velocity to infinity

You know the angular momentum equation that makes keplers second law work

L=rmv where L is angular momentum is r radius, m is mass and v is velocity.

Well according to that equation if we decrease the radius then either the mass or the velocity would have to increase (sort of how keplers second law works) right? Well then if we decreased the radius to Planck length or something extremely small, wouldn’t that mean that the object would have to increase its velocity (since it can’t increase its mass )so it could keep angular momentum constant?… Pls explain this to me (try to use equations) but any help would be helpful…Thanx in advance