See if your board isn't providing you a corrections facility of your marksheet, then I would recommend you to kindly visit a lawyer & file an affidavit regarding it & get it done in the Magistrate court only.

A lawyer will give you the proper description regarding the procedures you should follow up.

The affidavit will be valid & you can use it for any of the admission (as per the information available on different resources on Internet).

I hope this answer provides you some insight. Wish you a great eve!