If you live in the building of course you have a right to entry – and your key still works.
This to me seems a mix-up in communication. Changing a roller door in itself doesn’t mean the remote code will change. That’s all done by the door controller. If they changed that too then you might need the new code or even a new remote and that should have been given to you, if you are a resident.
But surely if they changed the door code/system but not all the remotes there would be many others in your situation? If other remotes are still working then you might have, by coincidence, a faulty remote unit?
Talk to you neighbours?