Something strange just happened, tell me what you would do!!!

I ordered a large online order for Christmas. I updated my current address. The company made a mistake and delivered to my old address, in the same building.

Tonight I realized my package tracking said delivered and my package was missing.

DH went to the door of our old place (where it had been mistakenly delivered) and was ignored as he knocked. He then used the intercom outside to try to contact the occupants that way and was ignored. Knowing they had my package, DH went back to their door and knocked and knocked until they answered.

They had not only opened my package, but they had taken out the individual items and looked through them. The package OBVIOUSLY has my name on it. They took the items out of the plastic bags (that are now missing). They finally turned over the package to DH with disheveled contents... did they try them on as well (WTF)?

I just am not exactly sure what to do. This is so odd. Obviously they were trying to keep the package and contents or they would have delivered it to my door, taken it to the manager's office, not opened it, or answered the door and handed it over immediately.

I emailed the manager, what are your thoughts?