ATM: need help with "Wrong answer"

I am getting “Wrong answer” after submission.
But I can’t find any combination of X and Y…all the combinations I tried locally returned the same error that passed the submit test. Please help.

def atm(withDraw, balance):
    fee = 0.50
    if withDraw % 5 != 0 or balance < (withDraw + fee):
        return balance
    else:
        return balance - (withDraw + fee)

def main():
    try:
        w,b = input().split(" ")
        w = int(w)
        b = float(b)
        balance = atm(w,b)
        print(balance)
    except:
        pass

if __name__ == "__main__":
    main()