Brightness keys functioning differently

Rajat. - Apr 29, 2016 at 04:52 PM
I own a HP Pavilon 15-R036TU Laptop.
The brightness up and down keys are functioning alternatively,means when I press the brightness up key it is decreasing the brightness and when I press the brightness down key, it is increasing the brightness of my laptop.
What could be the problem and what I need to do in order to resolve the problem.

Please help.

Waiting for your response.

Thank you.