Bearing "creep" is not normal and if it spins as freely as yours does in the housing then something is very wrong. It might even be that someone has fitted an incorrectly sized bearing in the past?

You could try using a bearing adhesive, which may work (for a short while), but you're only going to be hiding the symptoms of a greater problem. I would guess that, if it's been creeping like that for a while, the soft alloy of the housing in the sprocket carrier will have worn somewhat.

Probably worth trying a new bearing, perhaps with a bit of bearing adhesive; there might be just enough interference to hold it in place?

__________________