One PlayerPref not saving

I’m having an issue where all of my playerprefs save except one. Could you guys take a look at it?

        if (SceneManager.GetActiveScene().name == "zombies")
        {
            zombiesscore = scoreValue;

            if (zombiesscore > PlayerPrefs.GetInt("zombieshighscore", zombiesscore))
            {
                PlayerPrefs.SetInt("zombieshighscore", zombiesscore);
                highScore.text = zombiesscore.ToString();
            }
        }

P.S.: All of my PlayerPrefs are working in the editor, including this one. And they all work in the build EXCEPT for this one.

Remove the second parameter from this function:

  PlayerPrefs.GetInt("zombieshighscore", zombiesscore)

Re-write this statement as:
PlayerPrefs.GetInt("zombieshighscore")