late updation of 26AS

Dear Sir
In the AY 2014-15 my employer has given some incentive after deducting the applicable TDS. which was shown in my Form 16 but it was not reflecting in Form 26AS. My CA has filed the ITR as shown in Form 16.

Income tax department has raised demand unser section 143(1) of Rs 37000/-. Which was non known to me.

Now I have started filling ITR with self and came to know about the demand. upon checking the 26AS . it is now updated and matching with the form 16.

Now , it requested to you please guide me for rectification of out standing demand. How it can be materialised