Landlord changed locks before lease end

[Nick Klar]

We moved out early and turned in 1 set of keys, with plans to continue using/accessing our apartment with our remaining set of keys until our lease was up. Our landlord said there must have been a miscommunication because we arrived to access our apartment one day and found the locks changed and the apartment inaccessible. When we went to the office to get the key to our apartment, we explained we were still paying for the unit, but despite that were told we had to leave an ID with them and return the key when we were done to get back our ID. For our own apartment...

We do not feel we should have to pay for these ~3 weeks during which they broke our lease and removed access to our apartment. However I have a feeling the chances of them just saying “You’re right, here’s your money back” are slim. 

Any recommendations?