Proofs not considered under chapter vi a

Hi

I have received a outstanding tax demand from CPC for AY 2009-2010. I have received the intimation 143(1).

As per the document, my deductions under 80C are not considered by CPC. Due to this there is mismatch in the tax paid by my company and tax calculated by them. 

Could you please let me know, if just filing a rectification request is sufficient or if anything else has to be done.

Thanks in advance

Vishal