Sale deed Khatian mistake

I have brought a land of 2 Katta from Hahnemann Housing Development Limited in Asansol in 2016. Because of some leggal issues with other party they can not do mutation of my land. They are not giving possestion to me...They are delaying day by day till now. By chance I have searched in Banglarbhumi.gov.in that the khatian number mentioned in dag number for my land has no existance. It means the khatians of that dag number do not have my land's khatian number. I have asked the agent, he told me that he has asked the lawer, he answered that after opening of court they will see the matter, if there is problem in khatian in my deed, they will do a affidavit with the seller in court and will give me that affidavit as suppliment copy of existing deed. My question is affidavit in front of First Class Judicial magistrate is valid for changing khatian of my deed without registration or I should claim a rectified deed? rectified deed or affidavit has same validity? How can I get money back from them, as they can't do mutation or possestion, because of legal issues among different realstate companies? Please help me.......I am from a middle class family.