What the deal there is-
Ruger took the specs required for the latest then-upcoming military pistol trials as a basis for the new American pistol design.
Those specs called for an ambidextrous slide lock/release, so Ruger incorporated that into the gun.
But, after the decision was made not to submit for trials, the slide lock was tweaked to eliminate the occasional tendency to auto-close on an energetic mag insertion/reload.
That left it as you see- the right side is deliberately intended to NOT be usable as a right-side slide RELEASE.
It does still function as a right-side LOCK, in manually locking the slide back.
No point in calling Ruger or returning the pistol, it's doing what it was deliberately designed to do.
If you bother to return it, you'll be wasting their time & yours, and you'll get it back doing exactly the same thing.