Offered a voucher only to find out its a 2 years contract

I am so DISAPPOINTED at the service of this gym. They are lying to people and telling them that they are giving them vouchers to come and explore the gym only to find out that you have signed a contract with them and not a voucher. In 2017 I was offered a voucher to come and see the gym and the guy told me that I can sign the contract later once I liked the gym. He said I should sign the voucher form not knowing that it is a contract. Two years later i am told that I am owing the gym a certain amount and that my account has been handed over. These people are desperate to recruit people, please be aware of what you sign from them because they are a **** desperate for money.