Threatening by legal notice

Hi, I am Prakash. I found a job offer in Naukri and contacted the concerned person. When I met them, I came to know that it was not a real job opening, but a consultancy posted the ad. They assured me that I will be get interview calls, so I paid the registration fee. But even after 45 days I did not get any call from employers, so I asked them to refund my registration fee. Instead of refunding, they sent a legal notice with lot of lies. In the notice it was said that they arranged an interview and I failed to attend it. ( I have not received any mail or call regarding interview.) , it goes further that I went with my mom and used filthy words( which is the lie of this century). On top of all they claim Rs. 5 lakhs from me as I damaged the goodwill of the consultancy. I understand that just they are threatening. But What is the remedy.? I can not hire an advocate as I can't afford him. Can I file a police case against the legal notice with all available evidences I have? ( as the notice is threatening me)