A Purdue University engineering student said a CVS employee grilled him about his immigration status, even asking him for his visa, and denied over-the-counter cold medicines because his driver's license showed he was from Puerto Rico.

Puerto Rico is a U.S. territory and Puerto Ricans are U.S. citizens by birth.

José Guzmán Payano, a junior at Purdue, went to his local CVS store to purchase some Mucinex on Oct. 25. While completing the self-checkout, the CVS employee approached him and asked him for his identification, at which point he provided her with his driver’s license, which was from Puerto Rico. According to Guzmán Payano, the employee repeatedly told him that the store could not accept his identification, then asked him for his visa.

“She said she needed a U.S.-issued ID, Canada or Mexico license. That's when I tell her that was a U.S. issued license, and I didn't need anything else but that license," Guzman Payano told WTHR, NBC News’ Indianapolis, Indiana, affiliate. “When she asked me for a visa, I was in shock at that time.”

Guzmán Payano said incidents like this have happened to him before, which is why he carries around his U.S. passport in his backpack. Yet, the CVS employee would not accept his passport — which showed he was born in Puerto Rico — as a valid form of ID either and instructed Payano that he needed to provide documentation that verified his immigration status.

Guzmán Payano said he left the store without the medicine and returned a few minutes later to see whether a shift supervisor or a manager could assist him, but was once again told he’d need a U.S.-issued ID. Upon leaving, he called CVS to file a complaint.

"I was a little nervous," Guzman Payano told WTHR. “I was shook by what had happened.”

Though the incident occurred in late October, it gained momentum online after Guzmán Payano’s mother, Arlene Payano Burgos, wrote about it on her Facebook page.

“My son, or any other consumer, is not obligated to disclose his immigration status to any CVS employee! What caused this employee to ask him for his visa? Was it his accent? Was it his skin color? Was it the Puerto Rican flag on the license?,” Payano Burgos wrote in the post that as of Monday, had received more than 5,000 likes and more than 10,000 shares. “Whatever triggered her to discriminate against my son embodies exactly what is wrong in the United States of America today.”

CVS has since apologized for the incident and clarified that the store does accept Puerto Rican IDs as valid forms of identification that can be used to purchase cold medicine.

“CVS Pharmacy is committed to ensuring that every customer receives courteous, outstanding service in our stores and we have apologized to our customer in West Lafayette and his mother following his recent experience in one of our stores,” Amy Thibault, senior manager of corporate communications at CVS, wrote in an emailed statement to NBC News. “While we are confident that this was an isolated incident, we will be reiterating to all of our stores the correct procedures to follow when requesting identification that is required by law for certain transactions, as well as the forms of identification we accept, including IDs issued by U.S. territories such as Puerto Rico.”

However isolated the incident involving CVS may be, there have been other documented cases of U.S. businesses not accepting IDs issued in Puerto Rico. Last year, a Puerto Rican couple visiting California for their niece’s wedding said they were not able to check in to a Motel 6 because their IDs weren’t considered valid.

Both incidents underscore misunderstandings surrounding Puerto Rico’s relationship with the United States. The U.S. took control of Puerto Rico after the Spanish-American War of 1898. In 1917, Puerto Ricans were given U.S. citizenship through an act of Congress.

Yet, a 2017 poll found that only 54 percent of Americans know that people born in Puerto Rico are U.S. citizens.

“I guess I should be thankful that he wasn’t thrown in the back of an ICE van and interrogated, or worse,” Payano Burgos wrote in her Facebook post, referring to Immigration and Customs Enforcement. “What happened to my son today is not unlike what many other families have had to face since Trump was sworn into office and it’s completely unacceptable.”

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