Why here a arity errror and how to solve it

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9

yes, I have

(defn infix2 [[first-number operator second-number & r]]
  (if (empty? r)
    (list operator
          (if (list? first-number)
            (infix2 first-number)
            first-number)
          (if (list? second-number)
            (infix2 second-number)
            second-number))
    (if (< (get priorities operator) (get priorities (first r)))
      (list operator first-number (infix2 (conj r second-number)))
      (infix2 (conj r (list operator first-number second-number))))))

this one works also on nested ones like ( ((4 - 2) +2) * 3)