I already completed the main story and now I'm going for the side missions.

I went to the Steel Mill in order to complete the 'Hot and Cold' side mission, defeated all thugs, retrieved Freeze's tech piece, picked-up Riddler trophies and broke Harley's intercoms.

Once I was ready to get back to the outside, I found out that the gates I just crossed to get in Freight Elevator, the ones that connect with the rest of the Steel Mill, were now closed.

I tried everything; used all gadgets against it, thrown myself to the gate, used Detective Mode, verify files' integrity, restarted my PC... Nothing worked.

Now I'm trapped in Freight Elevator and I'm afraid I'll have to lose my progress. Can someone help me?