Kylie Jenner’s beauty empire might be in need of a makeover.

Kylie Cosmetics, the 3-year-old makeup company founded by the youngest member of the Kardashian-Jenner clan, is seeing sales sag as a majority of customers who have tried it once in recent months have not returned, according to an explosive new report obtained by The Post.

The privately held company, which is reportedly in discussions with Coty Inc. to acquire a majority stake for $600 million, has seen its sales decline 14% this year through May, according to Rakuten Intelligence.

Revenues peaked in November 2016, one year after the first product was launched, but two years later, in November 2018, revenues were down by 62%, according to Rakuten, which tracks online purchases.

The drop may be due to Kylie Cosmetics’ troubles getting customers to stay loyal, according to Rakuten, which relied on online receipts for 1.5 million customers.

The company found that a majority of Kylie Cosmetics customers — or 60% — shopped the brand just once from June 2016 through May 2019 when purchasing directly from the company’s website and from Ulta.com, according to the report.

Rakuten, a subsidiary of the $10 billion Japanese-based internet service company of the same name, did not track sales at Ulta Beauty’s brick-and-mortar stores, which began carrying the product in November.

“The Kylie Jenner brand is very valuable, but consumer loyalty is a huge piece of a brand’s value,” Jaimee Minney, senior vice president of Rakuten Intelligence, told The Post. “Her brand power brings people in, but the big question is whether it keeps people loyal.”

Indeed, Kylie Cosmetics was a huge hit in the year after its launch due in part to Jenner‘s famously pouty lips, which helped fuel excitement for the brand. When Kyshadow kits debuted in August 2016, they were gone in less than 60 seconds. And in February 2016, when Kylie Cosmetics released three new shades for her lip kits, they were up on eBay before the sale even ended with a starting price of $225 — almost 10 times their original $29 price tag.

More recently, the 21-year-old’s shoppers have taken to the internet to complain about lousy customer service, a lack of a refund or return policy, order mix-ups and quality issues associated with the products, according to a scan of websites that have published consumer reviews, including the Better Business Bureau and Ulta, the only retailer that has a partnership to sell the brand.

“I will never buy their product again,” one self-described first-time buyer, “Angel,” wrote in March on the BBB site, saying she spent $250 on merchandise and received only seven of the 12 items she ordered. Kylie Costmetics’ customer service didn’t help with her complaint, she said.

On Ulta.com, the $49 Momager Kit — so named after family matriarch Kris Jenner — recently showed 16 one-star reviews compared to 13 five-star reviews for the eyeshadow and lipstick combo.

“Would NOT recommend,” wrote Becca from Wisconsin earlier this year. “This was the first palette I’ve bought from Kylie. It was such a disappointment. The colors show up different on your lid and are very difficult to blend.”

Jenner’s lip products, which account for 69% of her sales, appear to be faring better than the newer lines, including eye and face makeup and makeup sets, according to Rakuten.

Sales of the lip merchandise have declined just 2.3% from June 1, 2016, to May 31, 2019, compared with an industry-wide decline of 5.3% for lip merchandise, according to Rakuten.

But sales of the brand’s eye and face makeup are down 29% and 8%, respectively, over a two-year period ended in May, according to Rakuten, which says demand for such products generally has risen 12% and 8%, respectively.

Kylie Cosmetics declined to comment for this story, but a person close to the business pointed to other reports touting the company’s growth.

Revenues grew by 9% in 2018 to an estimated $360 million, according to Forbes, which estimates that the company is worth at least $900 million.

Jenner has “already pulled cash from the profitable business,” Forbes said. That’s on top of the $1.2 million she reportedly makes per sponsored Instagram post, according to Hopper HQ.

What’s more, the company’s social media following has increased 11% to 25 million over the past six months, according to DA Davidson analyst Linda Bolton Weiser.

“Social media growth usually correlates roughly to revenue growth,” said Weiser.