1) A rectification deed should be executed after mutual consent of all the parties to the main deed. All parties to the original deed should jointly execute the rectification deed as well.
2)you may file a suit before a court under Section 26 of Specific Relief Act 1963. The law provides for relief to parties in case the real intention of the party is not properly reflected in the documents executed because of a bona fide mistake of fact.
. The court can direct the rectification of an instrument, if it is satisfied that the deed does not express the real intention of the parties. This relief is entirely discretionary.
3) There is no specific period of limitation fixed for filing the suit for rectification. Thus the residuary Article- 113 is applicable.you ought to file suit within three years from the date of the sale deed. From the date of the sale deed itself, the time starts to run for filing the suit
4) you have stated that you have already filed suit in civil court . wait for court orders
5) you can seek injunction restraining owner from selling the plot