Melvin Capital Management plummeted 49% in the first quarter. This once-star-studded hedge fund lost billions of dollars because it failed to go short during the retail trading frenzy set off by Reddit.

According to people familiar with the matter, the fund fell 7% last month, and the good momentum of rising nearly 22% the month before came to an abrupt end. The fund lost a huge 53% in January.

The fund founded by Gabe Plotkin is one of several companies that lost the most in a wave of retail investors rallying to push up stocks such as GameStop Corp. After that, Plotkin received $2.75 billion in life-saving money from Citadel, Point72 Asset Management, and other investors.

In February, Plotkin was asked to go to the US Congress to testify about the “war against the air.” He told lawmakers that the hedge fund industry will make adjustments to avoid a recurrence of such market events that have caused losses to its funds.

A Melvin Capital spokesperson declined to comment.