@ Rohit,
Performance/under Performance can difficult to prove.
If notice period of 30 days is applicable then company has to tender notice pay.
If termination order is bad it can be contested……………….even if company has tendered notice pay.
Model Standing Orders;Sec13,16::Service Certificate,FnF wages has to be supplied on the day of termination…………….
You should certainly approach an able Labor Law Consultant/Service matters Lawyer with all docs on record.
You may become member of employee’s/Trade Unions and be properly informed and protected………..