Fraud work done by future generali

As i have got a call from mumbai in november 2015 , person name was Mr arora and miss mansi joshi,they tild that they work in airtel company and they told me to install airtel 4g tower at my house terrace and for that i will get a rent from airtel company as Rs 30500 per month, with 1 year advance rent. For that i have to take a insurance policy of Future Generali and they told me for some terms and conditions as to not to share about airtel tower with future generali life insurance to get the rent. sir till now i have called them more than 100 times and they r not receiving my calls, even mr arora has switched off his phone since 2 months and miss mansi told me, that its in process, and she has blacklisted my number, even if i call her from another number, she never picks calls. Sir please help me to get my money of rs 50000 back. I have their all call recording and mails as how they were dealing with me. Please help me.