An IHOP restaurant in Maine retrained its employees after a waitress asked a group of black teens to prepay for a meal.

The eatery in Auburn, about 40 miles north of Portland, closed on Thursday for employee training and the waitress was disciplined, according to IHOP spokeswoman Stephanie Peterson.

The controversy started over the weekend after a waitress at the restaurant asked a group of black teenagers to pay for their meal beforehand.

This was witnessed by a person at a nearby table who wrote about it on Facebook.

“I heard them order their food, and they were respectful and were not loud or rude etc. We paid and sat there for a few minutes and I heard an employee tell the table that they were going to need to pay upfront and that it was ‘a new generation thing,’ Avery Gagne, who is white, wrote in his post, which was shared thousands of times. “I called over the group and asked them if they were seriously being asked to pay upfront and they said yes. So my father, mother and I stood up and began to question why this was happening.”

Gagne went on to write that he felt the teens’ race was an issue because the waitress immediately brought it up when trying to explain the situation.

“The woman took it upon herself to make this group of teens pay for their meal upfront because she considered them ‘high risk.’ I don’t care who has walked out on your establishment. That does not give you the right to determine who you believe is going to or not,” Gagne wrote. “My parents and I did not pay upfront for our meal, none of the tables around us prepaid for their meals. The fact that she stated ‘it’s not because of their color’ proves it all.”

The restaurant’s management took to social media, too, and offered an apology.

“Everyone has been made aware of these inexcusable actions and reminded how we handle matters correctly in the future,” read the post on IHOP Auburn ME’sFacebook page. “We have rectified the situation and can guarantee this is not what we condone to go on within our restaurant.”

The waitress’ actions weren’t racially motivated, manager Melvin Escobar told the Sun Journal newspaper, and added that the restaurant had been having problems with teens walking out of the restaurant without paying for their meals.

IHOP President Darren Rebelez also apologized, saying in a statement to CNN that the restaurant chain has “zero tolerance for actions that are or allude to discrimination of any type.”