The Children’s Hospital Colorado Foundation issued a warning Monday morning about a scam perpetrated by people claiming to represent the foundation.

The scam targets the Children’s Hospital Colorado Mighty Millions Raffle fundraiser. In the fundraiser, the foundation sells tickets for a $1.8 million house in Denver and thousands of other prizes to include cars, sports and events tickets, vacations, cash, gift cards and more.

“Please be advised that Children’s Hospital Colorado and its foundation do not make cold calls or authorize door-to-door fundraising by third parties,” said foundation spokeswoman Monique McCoy in a news release. “All of our partners are required to register with us, so if there is ever a question about a promotion or event held by third party individuals or companies on our behalf, please call Children’s Hospital Colorado Foundation.”

The number is 720-777-1700.