If you want a good fix, there is a kit for reparing it, just look for it, plenty of movies on youtube.
If you are looking for a cheap and quick fix I can tell you what I have tried, and it Worked great. I had my visit card box, in thin aluminium.. what the light bulb turned on. I have cut pieces o 1.5-2cc height and 0.5-0.7cm wide, put it against the bolt and curbed it on the bolt. It looked smth like this:
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Droped in the hole an tighten the bold inside. Worked great, it would not leak anymore.