Renting scam

Hey everyone,

I'm an erasmus student and I did a semester in Lisbon. I'm leaving at a residence that I booked through uniplaces, but I had another contract with the company of the residence. I'm gonna leave on 31st of January, but they are asking me to pay two more months, because they say that the contract is infinite and I should have notified them 2 months ago. I'm trying to reach a middle agreement, but they don't accept anything. I also have a deposit which they say they will give it to me after two months of paying rent while I don't live here. I don't know what to do, I'm a student and can't afford that. If I block my card will they sue me. Any advice would be very appreciated