"Sorry (I Didn't Know)" is a song by UK garage duo Monsta Boy featuring Denzie on vocals. It was first released in 1999 on white label, then officially released as a single the following year via Locked On Records and XL Recordings. The song reached number 25 on the UK Singles Chart, and number one on the UK Dance Singles Chart in October 2000.
Capital Xtra included the song in their list of "The Best Old-School Garage Anthems of All Time".
