Here are the steps to complain against a Navi loan: 1. Contact Navi Customer Service:91133–93177,Reach out to Navi’s customer service team either by phone, email, or through their website’s customer support portal. Explain the issue you are facing with your loan and request to file a formal complaint.Here are the steps to complain against a Navi loan: 1. Contact Navi Customer Service:91133–93177,Reach out to Navi’s customer service team either by phone, email, or through their website’s customer support portal. Explain the issue you are facing with your loan and request to file a formal complaint.