How to stop illegal registration of land already bought?

I am the respondent and currently in possession of the property. The plaintiff had sold the property long ago to others, and we purchased it in 2008 from those persons. Although the boundaries mentioned in the documents are the same, the survey number is incorrect. The plaintiff, who had forgotten about the earlier sale, was approached by land mafia and influenced to file a case against us to reclaim the land. While the case was still pending, the plaintiff transferred the property to other parties. However, in 2018, the case was dismissed with the judgment stating: "The case is dismissed for default." Now, the new parties (who received the property from the plaintiff) have filed a fresh case claiming ownership. They are also trying to fabricate a fake agreement suggesting that we, the respondents, had no objection to giving them the property and are now attempting to register it in their name. How can we stop this? Should I obtain a court order, or should I submit an application to the Registrar since the case is still pending?