在我的活动中，实际上我有一个按钮，然后单击按钮，我想生成FCM ...我想在重新启动应用程序并再次单击按钮时FCM应该每次都生成不同的令牌，但是每次都会生成相同的令牌

FirebaseInstanceId
        .getInstance()
        .getInstanceId()
        .addOnSuccessListener(new OnSuccessListener<InstanceIdResult>() {
            @Override
            public void onSuccess(InstanceIdResult instanceIdResult) {
                String token = instanceIdResult.getToken();// here same token is generating everytime
                System.out.println("Tokensss " + token);
                SharedPreferences sharedPreferences = Signupactivity.this.getSharedPreferences(cmn.SHARED_SPNAME,MODE_PRIVATE);
                SharedPreferences.Editor sharedPreferencesE = sharedPreferences.edit();
                sharedPreferencesE.putString(cmn.RegistrationTokenforFirebase,token);
                sharedPreferencesE.apply();
                tokenZ = new Token();
                SharedPreferences sharedPreferenceZ = Signupactivity.this.getSharedPreferences(cmn.SHARED_SPNAME,MODE_PRIVATE);
                String tokens = sharedPreferenceZ.getString(cmn.RegistrationTokenforFirebase,"1");
                DatabaseReference database = FirebaseDatabase.getInstance().getReference().child("" + Number);
                //  DatabaseReference myRef = database.getReference(""+Number);
                tokenZ.setToken(tokens);
                database.setvalue(tokenZ);
            }
        });