player prefs highscore

i have the highscore for my game sorted out but there is a catch. i have 2 modes and the high score in gamemode 1 is the same as 2 and vice versa. how can i fix this? I have the code and also in gamemode 1 i have the highscore text object called highscore compared to bestScore as i was trying to fix it.

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;

public class RushHighScore : MonoBehaviour
{
    public int score = 0;
    public int bestScore = 0;

    private void Start()
    {
        bestScore = PlayerPrefs.GetInt("bestScore");
        FinishedGame();
    }

    void FinishedGame()
    {
        print(bestScore);
        if (score > bestScore)
        {
           bestScore = score;
            PlayerPrefs.SetInt("bestScore", bestScore);
            print("New High Score; " +
                PlayerPrefs.GetInt("bestScore"));
        }
    }
}

It sounds like you are naming bestScore the same in both games.

PlayerPrefs.SetInt("aGameBestScore", bestScore)
PlayerPrefsSetInt("bGameBestScore", bestScore)

That should assign bestScore in each game to the specific archived best score.