I believe CIBIL is the only reason as NH , Amazon specifically mentioned in rejection 'Rejected due to insufficient/adverse of credit history being less than required policy norms'
Yeah a friend of mine also had the same minus 1 on it CIBIL through it employee CIBIL check where he secured job in bank. Now after couple of month it 830. It just means you don’t have a standing in CIBIL just get a job in a bank for fast CIBIL or get a secured card