Thanks everyone! I think it was Windows update issue. Today I installed updates and issue was fixed automatically. Thanks for taking interest in my issue and help.
I am using Dell Inspiron 15R Laptop. I installed new windows 10 for some purpose. Now I am unable to find the Bluetooth button in the settings.  I tried to get help online but could not find a solution that fix this issue. I could not find drivers for my Bluetooth. Please let me know how I can fix it or share driver's link. 
Unable to find Bluetooth after Installation of New Windows 10