I received a income tax intimation U/S 143(1) for the assessment year 2010-11 from CPC. As per the details mentioned I identified the error in my IT returns and want to submit a rectification request online. After logging into https://incometaxindiaefiling.gov.in/ I went to My Account->Rectification-Rectification Upload. I was asked to enter some computed details from the intimation from CPC. I am sure i am entering the correct details, but i am always prompted with the error saying that the details are wrong.
What further action can i take on this?