Anna Services - Electrical services non fulfilled

We have hired the services of anna services to undertake electrical services at our place on July **th (last month). He demanded an amount of **,*** as the cost of replacing electrical wires and a new switchboard. My parents are ** years old. My father is a patient has paid full amount as an advance in the hope that work will be immediately attended. After taking the money they are not responding to our calls. My father had a shock from the wires they left opened during testing due to which he needed medical attention. They cheated old senior citizens for money and exposed them to electrical shocks by not completing the work. We had to hire some other agency to get electrical services after they failed to respond to our calls or attend the work. I have Whatsapp conversations and missed call screenshots where they gave false promises and not attended works as well.