How do I remove ejector sprocket from Ender 3 Pro when there is no threaded bush to unscrew?

Hi

Filament is not properly being reliably fed through the ejector despite the stepper motor turning, It results in very thin uneven layers. The grip seems poor even when I disconnect the bowden tube.

I want to change the socket but can’t see how as there is nothing obvious fixing the sprocket onto the stepper motor shaft. It looks like it’s held on just by friction? (but firmly enough not to slip when the filament slips on it.

Is there a way to remove and replace it without damaging the stepper motor?

MalcolmH