Apartment bought out by another company

I live at what used to be known as Cortland Southpark Terraces. I have had a lot of issues with how apartment repairs have been handled (or avoided, rather) before they were bought out. Issues include a missing door to a closet in the secondary room, a shattered tile soap ledge in the bathroom, some water damage that appears in the kitchen ceiling, a microwave that doesn’t work, and a broken mailbox. These things have been broken since I moved in and not a single item has been fixed. Cortland tried to fix my mailbox and now it doesn’t lock at all. As a result, my mail has been stolen (including a wallet with cards and cash that was being mailed back for my brother). Now we can’t pay out rent online or with a check. The new owners want money order or cashier’s check (they only said check in the email), so I couldn’t pay when I walked up with my checkbook ready and on time. Now my rent will be late, I’ve had mail stolen, and all my repairs have never been fixed. I am beyond frustrated. Is there anything I can do to help get anything?? Be it repairs, money, SOMETHING. This experience has just been ridiculous. This is my first time renting, so this system is new to me.