Cucumber test cases fail when run together, but they pass when I run them individually

I am using Spring with Cucumber (and IntelliJ and Gradle). My test case fails when run together and passes when run individually. (The fails 2 out of 3 times, sometimes it works...)

I also tried to quarantine the problematic Scenario or Senario combinations, but no luck... I tried introducing @After and @Before hooks to reset the value of of the account value... I even tried switching the position of senarios, nothing helps...

I really hope someone can help me with this problem

The features:

Feature: Cash Withdrawal
  Scenario: Successful withdrawal from an account in credit
    Given my account has been credited with $100.00
    When I withdraw $20
    Then $20 should be dispensed
    And the balance of my account should be $80.00
  Scenario: Unsuccessful withdrawal due to technical fault
    Given my account is in credit
    But the cash slot has developed a fault
    When I request some of my money
    Then I should see an out-of-order message
    And $0 should be dispensed
    And the balance of my account should be unchanged
  Scenario: Unsuccessful withdrawal due to insufficient ATM funds
    Given my account is in credit
    And the ATM contains $10
    When I withdraw $20
    Then I should see an ask-for-less-money message
    And $0 should be dispensed
    And the balance of my account should be unchanged

And my stepdefinitions:

public class AccountSteps {

    @Autowired
    Account account;

    private Money originalBalance;

    @Given("^my account has been credited with (\\$\\d+\\.\\d+)$")
    public void myAccountHasBeenCreditedWith$(
            @Transform(MoneyConverter.class) Money amount)
            throws Throwable {
        account.credit(amount);
    }

    @Given("^my account is in credit$")
    public void myAccountIsInCredit$() throws Throwable {
        originalBalance = new Money(30, 00);
        account.credit(originalBalance);
    }

    @Then("^the balance of my account should be unchanged$")
    public void theBalanceOfMyAccountShouldBeUnchanged() throws Throwable {

        checkBalanceIs(originalBalance);
    }

    @Then("^the balance of my account should be (\\$\\d+\\.\\d+)$")
    public void theBalanceOfMyAccountShouldBe$(
            @Transform(MoneyConverter.class) Money amount) throws Throwable {

        checkBalanceIs(amount);
    }

    private void checkBalanceIs(Money amount) throws Throwable {
        int timeoutMilliSecs = 3000;
        int pollIntervalMilliSecs = 100;

        while (!account.getBalance().equals(amount) && timeoutMilliSecs > 0) {
            Thread.sleep(pollIntervalMilliSecs);
            timeoutMilliSecs -= pollIntervalMilliSecs;
        }

        Assert.assertEquals(
                "Incorrect account balance -",
                amount,
                account.getBalance());
    }
}

public class CashSlotSteps {

    @Autowired
    TestCashSlot cashSlot;

    @Given("^\\$(\\d+) should be dispensed$")
    public void $ShouldBeDispensed(int dollars) throws Throwable {
        Assert.assertEquals("Incorrect amount dispensed -", dollars,
                cashSlot.getContents());
    }

    @Given("^the cash slot has developed a fault$")
    public void theCashSlotHasDevelopedAFault() throws Throwable {
        cashSlot.injectFault();
    }

    @Given("^the ATM contains \\$(\\d+)$")
    public void theATMContains$(int dollars) throws Throwable {
        cashSlot.load(dollars);
    }
}

public class TellerSteps {

    @Autowired
    private Account account;

    @Autowired
    private AtmUserInterface teller;

    @When("^I withdraw \\$(\\d+)$")
    public void iWithdraw$(int amount) throws Throwable {
        teller.withdrawFrom(account, amount);
    }

    @Given("^I request some of my money$")
    public void iRequestSomeOfMyMoney() {
        int dollarsRequested = 10;
        teller.withdrawFrom(account, dollarsRequested);
    }

    @Then("^I should see an out-of-order message$")
    public void iShouldSeeAnOutOfOrderMessage() throws Throwable {
        Assert.assertTrue(
                "Expected error message not displayed",
                teller.isDisplaying("Out of order"));
    }

    @Then("^I should see an ask-for-less-money message$")
    public void iShouldSeeAnAskForLessMoneyMessage() throws Throwable {
        Assert.assertTrue(
                "Expected error message not displayed",
                teller.isDisplaying("Insufficient ATM funds"));
    }
}