Normally, a lamp does not have the warranty of the main unit, as it is intended for a certain lifetime (operating hours). In my opinion, this is a normal case of wear and tear. However, as I am not an expert, I recommend that you contact Digitec's customer service or BenQ directly for clarification. They will then be able to suggest a suitable replacement item.

PS: So explosion? It can happen that there is a bang. Did the outer casing shatter? And if so, was the main unit damaged?

Thank you for your answers, I will contact the manufacturer.
It was indeed an explosion of the lamp (sound volume about as loud as firing a shot with an assault rifle). I have not opened the housing. Splinters did not come out of the housing, but I assume that this happened inside.

As Brimstone said, lamps have a shorter warranty period of either 3-6 MT or a few thousand hours of runtime, whichever was reached first. A look at the manual will usually answer the question. There won't be anything you can do about it. If you want to press about the explosion, I would do it directly with the manufacturer... you have a better chance there.