Calico hamster with left-ear nick

I lost my calico Syrian hamster named Gizmo yesterday around 3pm. He's tiny, about 3 inches long, with a fluffy brown-and-white coat and a distinctive nick on his left ear, plus a tiny white heart-shaped patch on his belly. He tends to hide in cardboard tubes and loves sunflower seeds, so he could be anywhere around the Milwaukee Public Market area—specifically near 400 N Water St or along the Riverwalk by the Milwaukee Art Museum. This little guy means the world to me; we've been inseparable for two years, and I’m really worried he’s scared and hungry. If you’ve seen him, please reach out—I’ll come right away and bring his favorite snacks.