Trapped by Tours & Travel Holiday company named Imperial cruise services

A tours & travel company call people whose number they get from DMART, petrol pumps where people give their details for lucky draw coupons, invite to their offices to give them (invite couples) free gifts. Then they ask customers to spend some time in their seminars & they start advertising of their company. They show lots of lavish hotels &locations in their brouchers & advertise how they can provide them tours & travel plans & make lots of promises to people which are fake. They show EMI plans to just somehow swipe credit cards of people & swipe full amount. Then they sign agreement from people which says that Membership of this company cannot be cancelled & full amount deducted will not refunded. They do not give any membership kit, ID, SMS which they promise during seminar. This way they are trapping lot of Common people in the name of lavish holiday tours & travel destinations. I have taken membership but not used, since I do not believe in their services due to fake promises they made previously. How can I take legal action against them to refund back money.???