Your phone rings once and the caller leaves no message. Thinking you missed a call, you call the number back.

Someone answers or maybe you get a recording. You stay on the phone listening to the person or trying to decipher what the recording is saying.

Unknown to you, though, you have been connected to a line with high interconnect fees, similar to calling a 900 number, and a bloated phone bill is on its way.

The Federal Communications Commission warned consumers about this “one ring” scheme in an alert last week. It’s also known as a wangiri scam — Japanese for “one ring and cut.”