Black velvet evening gown with beaded belt

I lost my black velvet evening gown yesterday around 6pm after a charity gala at the Davenport Hotel on West Spokane Falls Boulevard in downtown Spokane. It's a floor-length gown, size M, from Adrianna Papell, with a slim silver beaded belt and a small rhinestone on the left shoulder strap. There's a tiny snag near the hem that I had repaired with clear thread, but overall it's in good condition. It was a gift from my grandmother and means a lot to me, especially since I have a big event tomorrow, so I’d really appreciate it if someone found it.