greedy for money

I signed a contract at gym by narin. The same month i phoned him an cancelled. No cards were issured or no fees were paid. I never visited gym to train but now a collection service phones me like everyday an say i owe 15000 are dey mad or what. Dat gym just gets ppl to sign up to ***** money. Even if u wana cancel u can not. U are stuck to pay an pay.