How do I politely move my neighbours hard board that they left infront of my front door?

I'm finding this uncomfortably weird😐. I live in a complex and have new neighbours - so yesterday I noticed long "hard board" right in front of my door. Can anyone tell me what would be the most polite way to move their hard board in front to their door without causing problems? It looks tacky in front of my door and want it gone. Please help. Thanks