Private Fainancers Charges high Intrest Rates on Personal Loan

Hi Sir, I based on mumbai and took the loan from Vote4cash company which is completely given the loan with verifying your social media profile and nominal documents which we provide while login also they done the phone verification.While doing this process they ask customer to install android application to log in there web site and apply the loan request,and ones we loged in to that application they hack entire phone contacts and randomly call for verification without user permission. Ones they approved the loan they transfer loan in user account and for one month they charges 49 % interest.As i took the loan from this company in year of 2015 and continually i paid the loan amount and interest.But from last two months i am into some financial crisis due to i failed to paid this dues and now they charge 500rs per day as penalty and late payment. Kindly suggest what i can do in this case?? as there no any legal agreement between me and company,only they will contact all my contact and trying to recover amount or harass them