The phone number, which Netflix has said will be edited out, appeared on a business card in the first episode of the series.
A businesswoman in the south-east South Korea is reported to be the owner of the phone number and told local media that she had been inundated with calls and texts to her phone "to the point that it's hard for me to go on with daily life".
WATCH: Have you caught up on the South Korean horror series?
She spoke to Money Today about the ordeal: "This is a number that I've been using for more than ten years, so I'm quite taken aback. There are more than 4,000 numbers that I've had to delete from my phone,"
"At first I didn't know why, but my friend told me that my number came out in Squid Game and that's when I realised," she added.
She is reported to have rejected offers of compensation up to five million won (£3,073).
A Netflix spokesperson commented on the phone number leak, saying: "Together with the production company, we are working to resolve this matter, including editing scenes with phone numbers where necessary."
What is Squid Game about?
Squid Game is the South Korean drama series that has got everyone talking. The unique horror show follows a group of contestants from different walks of life all competing in a game show that has deadly high stakes.
The official synopsis reads: "A mysterious invitation to join the game is sent to people at risk who are in dire need of money. 456 participants from all walks of life are locked into a secret location where they play games in order to win 45.6 billion won.
"Every game is a Korean traditional children's game such as Red Light, Green Light, but the consequence of losing is death. Who will be the winner, and what is the purpose behind this game?"
The series stars Lee Jung-jae as Seong Gi-hun, a divorced gambling addict who is invited to play a series of children's games for a chance to win a large sum of cash. He joins the other 455 players as they attempt to survive the physical and psychological twists of the games.
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