Consumer Court Case For Defective Product - Lawyer Required Or Party-in-person ?

I purchased a premium smartphone which later developed a sudden vertical green line on the display. The issue appeared on its own, without any recent physical damage, and is widely reported by many users as a known display defect. The manufacturer has also announced a free display replacement program for such issues.However, the authorized service center and company refused free replacement, citing old physical damage on the back panel that occurred months earlier and is unrelated to the display defect. I am not requesting repair of those physical damages, only replacement of the defective display.I first approached the company through customer support and the National Consumer Helpline, but the matter remains unresolved. I am now preparing to file a complaint before the District Consumer Commission, but I find the documentation process (affidavit, annexures, etc.) confusing and stressful. Is it advisable to hire a lawyer for such a case or handle it as party-in-person?