In the video, the clerk behind the counter gets into an argument with a customer.
Then she jokingly threatens to give the rest of the crowd his business card so they can call him up and make fun of him.
The customer walks out, walks back in, and then demands to get the information of the clerk so that he can report her.
The woman yells at the customer and then high-fives the person filming the video.
The video was filmed and uploaded by Curtis Lepore, who, according to his profile, lives in Burbank, Calif.
Lepore uploaded it to YouTube and put it on Twitter Tuesday.
Gamestop's Twitter account reached out for information about the incident Wednesday.
Gamestop's account has been responding to other users, who are sharing the video, saying they are "investigating the situation."
Gamestop's Facebook users aren't happy about it either.
Ryan Broderick is a reporter for BuzzFeed News and is based in London.
Contact Ryan Broderick at email@example.com.
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