Partnership in land purchased together

Dear all experts, Greetings of the day...!! In 2012 my dad and two other my neighbour purchased a land with the partnership of 1/2, 1/4 and 1/4 respectively. But due to unawareness and less education my father n other two partners, did nt asked the lawyer why he did not mention the share of each partner in Benama. Instead of mentionaing share in Benama he gave them a letter named as TAHREER on which share is mention. But these days i cross checked the papers and came to know that there is no share in benama so that we couldnt get our share and property will be devided into 3 parts while we paid the money for half of the property as per share. However other 2 partners are honest and ready to give us our share as it was discussed and agreed before purchasing of land. I would like to know that is there any solution to correct the same in govt. Land records so that we can get in written share of each partner. Also advise what to do as we have lost original paper of Benama only xerox we have and rest of the papers we have original with us. Its urgent so plz advise wht to do now.