The husband of missing coffee shop owner Amy Hillyard issued an appeal to keep her story visible on the six-month anniversary of her disappearance in March.

Chris Hillyard said in a video that investigators and supporters continue to search for answers and are focusing the search on specific areas, using drones to hunt for clues in places where Amy liked to hike and walk.

“The private investigator who’s worked on missing persons cases across the country called Amy’s disappearance one of the most perplexing cases he’s ever worked on,” Chris Hillyard said in the video.

WATCH: WATCH: Six months after Amy Hillyard disappeared in Oakland, her husband, Chris Hillyard, is asking people to keep her story visible as investigators and supporters continue searching for answers. (Bring Amy Home/YouTube)

The owner of Farley’s coffee shops in Oakland and San Francisco, 52-year-old Amy Hillyard was last seen on March 25, sometime after 2 p.m. near the 500 block of Radnor Road in Oakland.

Amy is described as white, 5 feet 4 inches tall, weighing about 120 pounds, with blonde hair and hazel eyes. She was wearing a white short-sleeved shirt, light-colored jeans and white sneakers with black stripes. She is considered at risk due to a medical condition.

It’s been six months, and her friends and family haven’t given up on the search.

“Still we all keep trying, and every day we wake up with a glimmer of hope that today will be the day that brings some piece of information that offers an answer to Amy’s whereabouts,” Chris Hillyard said.

A $25,000 reward for information on Hillyard’s disappearance is still in effect.

Supporters can stay up to date on efforts to find Hillyard at Bringamyhome.com, a site created by Amy’s friends and family. The site also includes various ways people can help with the search.