First off! Don't worry, this is normal!
Our motors have 'press fit' bearings. This means that the bearings are pushed into place with a hydraulic press. This process is common in the manufacturing world to ensure precision and to allow the bearing to be useful for its lifetime.
All materials will wear out over time and that press fit of the bearing will eventually loosen up (ever so slightly) that looseness is what causes the bearings in the motor to come free from the press fit and allow them to move in the bearing seat.
All of this is to say, this isn't a problem. The small amount of left to right motion is completely normal and is needed inside the motors for required manufacturing tolerance
Rip it up!