The chain last week attracted large crowds at its over 100 outlets in Malaysia by offering luxury prizes such as handbags from Louis Vuitton and Gucci and Apple smartphones.
Customers were required to find coupons hidden inside Chagee cups to determine if they had won.
But on Monday an online video went viral, showing a staff member going through the empty cups and putting aside the ones with the top prizes, according to the South China Morning Post.
People alleged that the staff’s action indicated that the lucky draw was rigged.
Chagee responded by telling social media users to remove the video "immediately", which further fueled public outrage.
"Chagee [asked me to] delete the video or else I will be cited for legal action," X user Naquib said in a post seen by almost 6 million people.
The chain’s Malaysia social media page was seen with hundreds of comments, with some calling to boycott the brand, same as they had done earlier with other U.S. chains such as Starbucks or McDonald’s for believing that they were connected to Israel in the Middle East conflict.
Facing backlash, the milk tea chain decided to apologize to defuse the tension, saying that it "deeply regret any negative experience" over the incident.
It said the behavior shown did not reflect the standards that the brand holds itself to. "We are currently conducting a detailed investigation to better understand the situation and, if necessary, will take appropriate action in line with our values," Chagee said in a statement.
It changed the lucky draw mechanism to using QR codes instead of physical coupons.
Established in Yunnan, China, in 2017, Chagee has experienced rapid growth in Malaysia, thriving despite stiff competition from Taiwanese brands like Chatime, Gong Cha, and local favorite Tealive.