Type mismatch error of Unit instead of Int (Scala)

I'm new to Scala and I'm trying to define a tail recursion factorial function like this:

def anotherFactorial(n: Int): Int = {
    def factHelper(x: Int, accumulator: Int): Int = {
      if (x <= 1) accumulator
      else factHelper(x - 1, x * accumulator)

    factHelper(n, 1)
    }
  }

But it gives me a mismatch error saying that it found a Unit type instead of an Int and I cannot see how, I've checked other Scala questions with the same error (like this one: Scala Type Mismatch Unit Instead of Int) but doesn't seem I'm making those mistakes.

This is the error message:

type mismatch;
 found   : Unit
 required: Int
  }

Wrong brackets. You have:

def anotherFactorial(n: Int): Int = {
  // the body with only def is Unit
  def factHelper(x: Int, accumulator: Int): Int = {
    if (x <= 1) accumulator
    else factHelper(x - 1, x * accumulator)
    factHelper(n, 1)
  }
}

rather than

def anotherFactorial(n: Int): Int = {
  // the body with only def is Unit
  def factHelper(x: Int, accumulator: Int): Int = {
    if (x <= 1) accumulator
    else factHelper(x - 1, x * accumulator)
  }
  factHelper(n, 1)
}

I recommend using some formatter like scalafmt often (e.g. on compile) to spot issues like this immediately. Additionally if you annotated factHelper as @scala.annotation.tailrec compiler would fail as this wrong bracket makes it non-tail-recursive, so it would also help spotting the issue.

Type mismatch error of Unit instead of Int (Scala)

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