That is a sign that you are addicted to gambling. Unwanted gamblers can certainly limit themselves to gambling. And you do not have it, limiting yourself not just want it, but you have to act, you have to do it. Because speech alone will not be enough.
Yes it is a sin of addiction now only he can control his feelings or else it will ruin his life. Making limit is easy but stopping your game at the right time is very tough. That is why he is depositing again and playing after losing his limit of amount.