The White House should investigate Kellyanne Conway for her statements on Fox News last week recommending people go out and buy Ivanka Trump’s fashion line, an Office of Government Ethics official wrote Monday.

In a letter released by Democrats on the House Oversight and Government Reform Committee, Walter Shaub, director of the office, wrote that Conway’s comments on the show should be investigated thoroughly. While White House press secretary Sean Spicer has said Conway was counseled for giving a “free commercial” telling people to “go buy Ivanka’s stuff,” the ethics office hasn’t seen evidence of any reprimand.