A RECTIFICATION DEED is to be executed for the correction of Survey Number. No worry. It is maintainable.
Both parties may prefer rectification deed and sign IT, and register IT.
If seller is not agreeing then either there is some reason or majboori or something fishy..
You may alongwith elders of the family, competent and experienced well wishers, seasoned community leaders, PIP’s, helpgroups, find a very able LOCAL counsel of unshakable repute and integrity specializing in concerned field of law e.g; Revenue/Civil matters as in your case, and well versed with LOCAL applicable rules, precedence, latest judgments etc …. and worth his/her salt, and your counsel can advise you after examining all property related docs, inputs and even help so as to defend your long term interest.
There are such very able counsels at each location.
Check for such counsels at LOCAL O/o Tehsildar/CIVIL courts..HC,SC
Your counsel may opine for declaration suit..if the need be.
In future preferably let your elders of the family, competent and experienced well wishers, and your counsel help in draft and checking the deed.