I cannot call another class

In my main class I have this input method:

 private static void userInput(char[][] board){
        System.out.println("Select your pos 1-9");
        int roundCount = 0;
        while(board != null && roundCount < 10){

            int pos = new java.util.Scanner(System.in).nextInt();
            /*while(spielerPos.contains(pos) || comPos.contains(spielerPos)){
                System.out.println("Position besetzt. versuchen Sie bitte nochmal!");
                pos = new java.util.Scanner(System.in).nextInt();
            Random rdm = new Random();
            int comPos = rdm.nextInt(9) + 1; //the AI can replace this line to inject pos
            /*while(spielerPos.contains(comPos) || spielerPos.contains(comPos)){
                comPos = rdm.nextInt(9) + 1;
            caseDecision(board, pos, "human");
            caseDecision(board, comPos, "com");



The very last line crl.trackPositions(); shall bring me to operate another class:

static String winOrLose(List topRow, List midRow, List botRow, List leftCol, List midCol, List rightCol, List diagonal1, List diagonal2){
        new Tic_Tac_Toe(); //calling my main class here

        List iWon = new ArrayList<>();

        for(var l: iWon){
            if(spielerPos.containsAll((Collection<?>) l )){
                return "you won!";
            } else if (comPos.contains(l)){
                return "com won, try again";
            } else if (spielerPos.size() + comPos.size() == 9) { //board is full
                return "we're all tied";
        return "have you seen me";

But my program does not display anything from the other class (it was supposed to pring who was the winner, me or cpu) - it simply ends itself once I completed the 10th round with a cpu.
Could anyone kindly point me in the right direction?
My full codes are here TTT_experiements/ColRowLists.java at master · morry239/TTT_experiements · GitHub and here TTT_experiements/Tic_Tac_Toe.java at master · morry239/TTT_experiements · GitHub (this is my main class).