UVB bulb issues

I have two of the Arcadia Pro T5 UVB kits for my cresties. However the bulbs stops working in them after about a month or so after replacing it (this has happened like 5 times now).

My boys are in glass exo terra terrariums, which have a mesh top, so I was wondering perhaps if my auto mister was getting it wet and maybe this would break the bulb? But I’ve tried angling to misters more on a downwards angle so it defiently won’t be spraying the bulb directly and it has still broken.

Perhaps humidity is causing the issue? But these UVB kits are made specifically for reptiles such as crested geckos so surely thats not the case?

Any advice please??