Sale of gifted property without prmission

All respected ,

A and B are scheduled cast persons. Both were gifted with landed property. A and B sold the property to X without permission of Government. When sale deed of gifted property came to the knowledge of Government, Government entered its name to the property. On 7/12 extract, Government is the owner of the property. Now X wish to sale that property.  Further, whareabouts of A and B are not known. In such set of circumstances, what remedy is availabel to X. Pl guide.

Thanks.