Valecha Engineering — fd entitlement declined/not responded

Despite my parents' frequent reminders and personal visits to their office the company is not returning the FD for Rs 3, 00, 000 with interest which was deposited in May 2013 and matured in May 2015.They are very sr citizen and their retirement savings on which they survive on has been withheld by the company.
The staff at the company are not cooperative and keep giving false promises.