How to create a HighScore using playerprefs based on passed time?

Hello everyone!
I am currently creating a game where the score is passed time. When the player dies a restart panel is shown and the timer no longer updates. But my highscore is not working and I don’t know why.

void Start()
{

    HS.text = PlayerPrefs.GetFloat("HighScore").ToString();

}

   


void Update()
{
    if (restartPanel.activeInHierarchy == true)
    {
        if (timeLeft > PlayerPrefs.GetFloat("Highscore", 0))
        {
            PlayerPrefs.SetFloat("Highscore", timeLeft);
            HS.text = timeLeft.ToString("0");
        }
    }
    if (restartPanel.activeInHierarchy == false)
    {
        timeLeft += Time.deltaTime;
        startText.text = (timeLeft).ToString("0");
    }
   }

In Start function you read High(S)core with a big S letter and in the update, you save it in High(s)core

so Read : HighScore
and write : Highscore
Because of not setting the big letter at “S” you write and read two different PlayerPrefs