How can 👁️Sauron command the 💀Nazgul without the Ring?

[BalrogRingDestroyer]

His whole point of making the Ring was to subdue the wills of those who took the other Rings as them using the other Rings would make them vulnerable to being controlled by him.

However, he lost his Ring when Isildur cut it from his hand and he never ever got it back. Isildur took it and then lost it in the water when he died. Deagol found it and was killed by Smeagol. Smeagol had it for centuries until he lost it and it was found by Bilbo. Bilbo gave it to Frodo. Gandalf briefly held it when he threw it into the fire. Later, Sam got it when he thought Frodo was dead. Finally, Smeagol got it back from Frodo right before the Ring's destruction. Sauron never ever possessed the Ring after being defeated by Isildur.

So how does he ensure that the Nazgul don't mutiny?

 

[Squint-eyed Southerner]

Short answer: he held their rings, to which they were enslaved.

Slightly longer answer: the Ring was his, he made it; a great deal of his innate power was bound up in it; as long as it existed, whether it was on his finger or not, the evil force it exerted would still be in effect.

We don't really know all the powers of the Ring. The Three are, of course, a special case, but I think the fears of the Elves represent, in mythical terms, the fear of being "read" and controlled by an outside and inimical force, that runs from Homer to Orwell and beyond. It's still with us today.