Lost black Labrador retriever named Max with bright orange collar in Deering Oaks Park.

My beloved black Labrador retriever, Max, got loose during our walk in Deering Oaks Park on October 12th and hasn't returned home. He is about 4 years old, has a bright orange collar, and the tags have my contact information. Max is friendly but may be scared. Anyone who sees him, please call me ASAP!