Agriculture land's map not created & neighbor land encroached

we have have a agriculture land which was acquired by my grand father and after assistant commissioner approved us that land taking penalty amount. but that lands map has not been created now neighbor land owner acquired that land and telling that there is a no land for you, we try to Measure our land from servery department but they told that there is a no map of your land so we can't measure, we lost our land i am sure there is a land. so how can we get measure that land and make that land map