Check the following:
 

•       Is the light bulb in the fixture loose?... if so tighten the bulb.

•       Is the light bulb in the fixture burnt out?... if so replace the bulb.

•       If it is a 3-way or 4-way switch, check the associated switches... if one of them          is partially switched the others will not function.
   

Is your switch still not functioning?​
 

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