TDS Demands Old

TRaces portal of my client shows demand for earlier years frm 11-12 to Fy 18-19 which includes late filing fees and also demand due to incorrect PAN Client doest have and details of TDS challans , ACk copy of TDS return filed by earlier CA and earlier CA isnt providing anything. Challan details are required for conso file request how to go abt this. Can anyone guide