A group in Denver that helps immigrants and refugees keeps getting late-night phone calls from people who want President Trump to build a border wall.

They couldn't figure it out - until they realized their phone number is one digit away from the number on a dramatic sounding ad on the Fox News Channel.

"President Trump is demanding an end to chain migration, an end to the visa lottery, and the building of a wall to secure our Southern border. Please pick up the phone now and call," the ad says before giving a phone number. You can see a clip in the video above.

But if you dial incorrectly, by just one digit, you end up reaching the offices of Joining Vision and Action.

"They hear a voice, that's a live voice, and then they become a little confused," Sarah Hidey, who works there, tells Next with Kyle Clark.

Joining Vision and Action is a progressive group - not exactly "build a wall" cheerleaders.

The ad tells people, "We must make our voices heard. Again, call...," and then people do, over and over again. d they do. Over and over again.

"I got a lot of people who were like, mumbling, kind of like, 'Oh, what? I don't know what I just called.' And i got a lot of those. I answer probably five to seven in a row," Hidey says.

Eventually, Hidey came up with an idea.

"I thought it would be humorous to answer as if I was a recording, and say, 'Hi. Thank you for calling to voice your support for refugees and immigrants."

If you're curious who people are supposed to be calling if they dial correctly... ads like that are used to collect information from people who don't usually get involved in politics and donate. They're people who might be moved by a dramatic sounding ad on a cable news channel.

Moral of the story: dial carefully, everyone!