Meghan Markle's suit during her evening debut did not impress some critics.

On Thursday, the "Suits" actress and fiancé Prince Harry attended the annual Endeavour Fund Awards in London. It was Markle's first evening event with the Duke, and she opted to wear trousers from Kate Middleton's favorite brand, Alexander McQueen.

Markle looked chic and fab in her suit, but not everyone agreed that her ensemble was perfect for the event. Some took to social media to express their disappointment over her clothing choices, Fox News reported.

"When you keep hoping she'll make better choices," one social media user wrote.

"I am disappointed. She looks good in dresses. Why not wear one?" another user said.

"Can't she please wear a dress to one of these engagements?!" Elieen Carter commented.

"I've enjoyed her wearing pants but would like her to mix it up a bit. A dress here would have been nice. Not a fan of this look," Karen James suggested.

Markle has impressed many royal fans when she attended her first royal engagement with a modern princess look. Unfortunately, when she stepped out with Prince Harry and the rest of the royal family members to attend Christmas service, she made a fashion faux pas in her choice of hat, which many likened to chocolate or a rude emoji.

The criticisms continued when the "Dater's Handbook" star joined Prince Harry in Brixton. Some noticed her messy bun hairstyle, which they considered not fitting for a royal. A number even suggested that the royal bride-to-be should redo her hairstyle.

Some wonder when Markle will get a hairstylist or some wardrobe help. Another called her hairstyle an "untidy knot."

"The untidy topknot was not becoming," Judy wrote. "Ok these two need to grow up they aren’t teens or in their 20's anymore. Harry is early 30's and Meghan is almost 40. She can't keep pushing the envelope, eventually the Queen is going to step in and take her to task. We need dignity."

Just like Markle, Princess Diana's evening debut dress became a hot topic of discussion. The late Princess of Wales stepped out in a low-cut Emanuel gown at the time. It slipped down and accidentally revealed her cleavage when she stepped out of her Rolls-Royce.

In addition, some were not pleased with the color of her outfit. Princess Diana and her fashion designer opted for black, which royals only wear for gloomy events like a funeral.

"We were very young and we had no press adviser. We didn't get any advice from the Palace. She trusted us and we did our best. We thought she looked perfect – young and beautiful and elegant," Elizabeth Emanuel said after receiving angry letters from the public due to Princess Diana's gown.