Rogelio Villarreal knew nothing about the French jeweler Cartier, he said, when an ad popped up on his Instagram feed last December. He clicked on it, perusing the pages of bling and other luxury items, including handbags, watches and necklaces, each listed for thousands of dollars.
Then Mr. Villareal, who lives in Mexico, noticed a pair of earrings: slender studded 18-carat rose-gold cuffs lined with diamonds, priced at just 237 Mexican pesos, or about $13.
He bought two pairs. Later, the price for the earrings was adjusted on the Cartier website to 237,000 pesos — more than $13,000.
The purchase initiated a monthslong tussle between the surgery resident from the northern state of Tamaulipas and the storied brand, with hundreds of social media users following along — some cheering, others taunting — and even a Mexican senator weighing in on the dispute.
“I was amazed to see how much the necklaces cost and so on and I said: ‘Someday,’ until I saw the earrings,” Mr. Villarreal, 27, wrote on social media. “I swear I broke out in a cold sweat.”
Within a week of the purchase, Mr. Villareal said, Cartier began a series of attempts to cancel the order, initially saying that the earrings were not available.
