Farming land have diffence in paper and map

Dear Sir,

I have property in Uttar Pradesh Lucknow. Last Year  I bought it from my relative and that time I did investigate if there is any problem in papar I pad the mount as per the paper as its 72 Mandi. But when I saw on site it's less and on MAP also it 60. I hired the lawyer and he is saying as per MAP and other landlords land size are correct so we can not do anything.

Please advise.