False implication in a case by policemen

I'm running a restaurant in Delhi. On 15th of June a constable from R.K.Puram police station arrived at my restaurant told me that my father has to come for a statement in a case filed against him. I've informed him that my father is undergoing treatment for cardiac problem will come on 17th June. On 17th June early morning I've got a phone call from a lady SI threatening me that if my father doesn't come to investigation before 12pm she would drag him from our house. My father sent her a msg on advice from one of his friend who worked for police that my father would file a complaint with recorded evidence with NHRC. On 19th June she sent a notice that I'm involved in sending obscene messages to some girl. My advocate got the FIR copy from the police station where there is no mention about me nor the numbers used for sending obscene images were not mine. The SI had been pressing me to attend investigation but in mean time on 30th june I had approached commissioner of police, NHRC and central vigilance committee with detailed complaints which are under process. On 17th July I've got call from the same SI threatening me of dire consequences if I don't come for investigation she is threatening to seize my properties I'm scared now what should I do legally which will give me and my family immediate relief. I had been knocking the doors of NHRC where the matter is still under process.