So they gave 3 rings to elves

They aren't. They're just rings that give special powers to each race, but would all be controlled by Sauron with his one ring to rule them all.

3 was just for the elves (Círdan, Galadriel, Gil-Galad); 7 for the dwarven kings (Durin's folk, Firebeards, Broadbeams, Ironfists, Stiffbeards, Blacklocks, and Stonefoots); 9 for leaders of men.

This entire show is written by people who think they can write Tolkien better than the man himself.

In the actual lore, the Three were created by Celebrimbor alone; Sauron didn't even know they existed until he created and put on the One.

I don't remember the exact conversation, but maybe he was just saying something about the power of the three elven rings in general, and not that when you made magic rings, they had to be in multiples of 3.

Maybe he (or the writers) meant the power of the three groups of rings. Elves, Dwarves, Humans. Otherwise I cannot make sense of it.

I havent even watched this show. But curiously looked on here.