What is the reason stated in the termination order? Did the company level any charge and/or issue any show cause notice? What was the heartburn and why the negative feedback is being issued? The negative feedback being issued is verbal or in writing? Can you produce any witness from any of the employers/consultants that they have not considered your candidature due to negative feedback from M/s..........?
If there were any issues/altercations/internal problems you should have consulted elders in the family, competent and experienced well wishers, lawyer/law firm before hand and must have diffused the situation or you could have issued notice of resignation and arranged for your next venture, in the interim.
If the order of termination was bad, you could have contested it.
Now you may take up the matter with the good offices of your appointing authority, MD, CEO, Head-HR, and even your line management and settle the matter once for all. You shall need to apply your persuasion, persistence, reasoning skills, and remain gentle, and thus avoid negative feedback in future.
If you can you must trade the termination order with resignation in back date.
Or you may approach a competent and experienced service lawyer with all records and you lawyer after assessing the merits may advice you to issue a legal notice and then approach suitable forum e.g. o/o Labor Commissioner etc.