First of all, you don't need to worry, it is a mistake from the University, this can be taken at a legal level also, if the discrepancy impacts your appointment. You have not committed any error or falsified any document.
Is it the DBRAU university? Who is asking form the new marks sheet with 1 mark less ( the documentation verification team or the university)? If the university is same, there are complaints on consumer form sites regarding similar issues.
1. You can contact the Unvieristy registrar and explain your predictament
2. Or you can meet them directly with all your records
Dr. Bhimrao Ambedkar University, Paliwal Park , Agra (U.P.) 2820040).
3. you have an option to raise a complaint (http://dbrau.org.in/Complain.aspx)
4. Is there anyway you can contact the recruitment in-charge related to the department you are going to join.
If so, please contact them and explain your difficult position and seek their advise or help to resolve the issue.
5.Have your tried contacting the administrative staff at the college where you graduated from, usually the office staff will have practical ideas and the ways to get things rectified as they would have handled similar issues.
5. If the above does not help or the deadline is close, I would contact a good lawyer to help out with this issue because I would not want to lose the chance of getting a central government job because of an university error.