A New York couple who were supposed to return from the Dominican Republic last month have not been heard from, according to family who said they are trying desperately to find them.

Orlando Moore and his girlfriend, Portia Ravenelle, left for the Dominican Republic on March 23 and were supposed to return March 27, Moore's sister, Lashay Turner, told NBC New York.

The couple, from Mount Vernon north of New York City, had parked their car at Newark Liberty International Airport in New Jersey before their flight, and family members said the vehicle is still there.

Turner said officials in the Dominican Republic said the couple didn't make their flight after checking out of their hotel in Samana.

An official with U.S. Customs and Border Protection also told the family that Moore didn't make his flight back to the U.S. A spokesperson for the department said CBP doesn't comment on international travelers' specific cases due to privacy concerns.

"When these things happen, you always think of the worst, but we are hoping for the best," Edith Walters, Moore's grandmother, said.

A U.S. State Department spokesperson said in a statement to NBC News that it is aware of reports of a couple missing in the Dominican Republic. "We stand ready to provide appropriate assistance to U.S. citizens in need and to their families," the spokesperson said.

The latest photo posted on social media of Moore and Ravenelle shows the pair on horses, NBC New York reported.