In July, Trai had announced draft regulations on consumer protection and redressal framework to protect the interest of users.
The regulator had proposed providing bills to pre-paid users under the proposed Telecom Consumer Protection Regulation.
The regulator had also asked all service providers to set up compliant centres within 60 days of implementation of the proposed regulation. It said these centres should provide service to consumers in regional languages.
Apart from a complaint centre number, operators should provide a separate number for providing general information to consumers, the Trai had proposed.