When a woman in Oregon, Ohio, placed an order over the phone for a large pizza, the 911 dispatcher on the other end of the line told her she had the wrong number.

But the woman was insistent. “No,” she said repeatedly. “You’re not understanding.”

Eventually, the dispatcher caught on. “I’m getting you now, O.K.,” he said, according to audio of the Nov. 13 phone call released this week, before asking if the perpetrator was still there.

Placing a coded call is a common way domestic abuse victims can signal for help without jeopardizing others’ safety, according to the National Domestic Violence Hotline, which provides lifesaving tools and support to abuse victims.

This time, the technique, which the caller in Oregon was using to report an attack on her mother, resulted in the arrest of Simon Lopez, who faces a misdemeanor domestic violence charge, Chief Michael J. Navarre of the Oregon Police Division said on Saturday.