Question about Netatmo Welcome

Since the camera has no actual heat sink, or the housing serves as a heat sink, increased temperatures are possible. Not 45 degrees in my case, but well over 30.
So I don't think that's a cause for concern.

mine also gets warm, but works perfectly.

My camera is also quite warm. But it works perfectly and the built-in components have to dissipate the heat somehow. I think about 40-45 degrees is OK.