As you can see, The steel part of the clock reflected in to the glass part. How can i fix it?
It’s not a problem of reflection. The metal material is bleeding onto the glass part because of the Subsurf modifier. It happens all the time. So much that we almost call this an expected behavior. 
You have 2 solutions:
Either you separate the glass from the metal, or you increase the crease on the edge loop where the 2 materials meet. [SHIFT E], 1, [ENTER].
I don’t know why exactly it works but to increase the crease is what I usually do when a material bleeds onto another. If it affects the shading or the shape, you can reduce the crease. It think that 0.25 is even enough.