Yes you can file a suit seeking compensation for mental and physical harassment by the bank authority which they did it intentionally for that period under which you were under their scanner.
As an employee you have the rights for a chair and table.
The harassment made by the bank by not providing you with a chair to sit and work in the office is agaisnt the labor law as well as contrary to the constitutional rights and also violation o human rights.
You can initiate necessary legal proceedings as per different provisions of law for compensation as well as reliefs under various law.