Playing games depends on luck. How should I reply?

You can reply like this: I don't deserve it.

The answer in just a few sentences also shows your high emotional intelligence. If you deny it, it will make people feel too hypocritical, because your family is happy and your career is successful, and you should be the big winner in life. If you admit it, people will think that you are too modest.

And your "I'm flattered" is the most ingenious answer, neither admitting nor denying it, but it makes people feel that she is modest. It's really a wonderful answer.