In the message, the 25-year-old man had provided information about the girl who he had met during his visit to the red light area.
He was then called to the DCW office where he provided more details about the girl's whereabouts. The commission then contacted the police.
A team of Delhi police and DCW officials rescued the girl from brothel number 58 late last night.
"The victim said she was a native of Bihar and that both her parents had expired while she was very young," the DCW said in a statement.
Though she claimed to be aged 20 initially, she later said the brothel owner had instructed her to misstate her age during police raids.
"The girl said she was kidnapped from her aunt's house by an unknown woman who sold her to the brothel owner at GB road at the age of nine. She was asked to entertain her first customer at the age of 11.
The girl had made attempts in the past to escape from the brothel but was caught every time because of the CCTV cameras installed there.
The girl had expressed her desire to escape with this man who had visited the brothel. But the brothel owner overheard their conversation and the man was beaten up.
"He is the same man who informed us about the girl," said a DCW official.
In her statement to police, the girl said her life was in danger and that she wants to take legal action against the owner of the brothel.
The Delhi Police is yet to register an FIR in the matter.