The safeguards that are available under privacy laws in India against call recording by individuals are not clearly defined. There is no law that makes recording a call by an individual on their device illegal. Talking on the phone is not about data protection, but more about my privacy. You may certainly file a police complaint to that effect and also issue her a formal legal notice of such threats.
You may independently approach the police station and lodge a complaint as against both the illegal threats and the mental harressment caused due to her conduct. Validity of Call recording without informing the Participant. The recording of conversations depends upon a fact-to-fact basis and the nature of their recording method. Tape recordings have been time and again held valid by the courts in India, but this does not automatically make tape recordings valid.
Tape recordings have been held valid when mandated by the government or when procedure established by law has been duly followed. In this case, the Indian Telegraph Act, IT Act, and Art. 21 are the procedures established by law. In a nutshell, statutory laws are not very clear as to when telephonic conversations may be recorded. In India, telephone tapping has to be approved by a designated authority. It is illegal otherwise. The Central Government or State Government is empowered to order the interception of messages per section 12 of the Indian Telegraph Act 1885. Rule 419 and 419A set out the procedure for interception and monitoring of telephone messages. There is a provision for a review committee to supervise the order of interception.
Reference: The Central Government or State Government is empowered to order interception of messages per 12, section 5 of Indian Telegraph Act 1885. Rule 419 and 419A – 202100499-20210007-978