As others have mentioned, contact the property manager. A short term solution might be to pick up some flood barriers to use around the door--like these. They aren't perfect but we use them on our screen door in the summer to help keep water from flowing in during tropical storms.
I live in a ~basement~ garden unit in chelsea with a little patio out back and was prepared for the idea of it raining so hard that it floods and water comes in through the back door. What I wasn't prepared for was water to just start leaking in out of the wall.
My theory is that the gutters on the house next door are clogged which caused water to pool in their backyard which came in through the foundation. Not fun at all.
Anyway, so far as practical advice, I bought some of these flood barriers from home depot so that if it happens again I can contain the water and soak it up. I also got a shop vac in case things get really bad.
Quick Dam QD65-2 5' Barrier Water Flood Dam Bags, 2 Pack, Black https://www.amazon.com/dp/B0085S19D6/ref=cm_sw_r_cp_api_glt_fabc_NTNSAGRXZ5J5HAF7Z1HR?_encoding=UTF8&psc=1
These flood barriers don’t take up any space when they’re dry and have saved my basement multiple times.