Hey, it happens: Sometimes fans mix up celebrities... and such was the case for Reese Witherspoon, who was recently mistaken for Carrie Underwood.

The 44-year-old actress revealed the mistaken identity incident via social media on Sunday (June 28).

"To the woman in the parking lot who just asked me if I was Carrie Underwood: You officially made my day," Witherspoon wrote alongside a smiling heart emoji.

Underwood quickly responded to the tweet. "YOUR day?!?!?!?! That lady just made my whole life," the 37-year-old singer wrote.

The fan who mistook Witherspoon for Underwood, Noha Hamid, explained what happened in a TikTok video.

"The craziest thing just happened," she told the camera. "I'm with my husband in Nashville, Tennessee, eating at a barbecue place and I swear I see this lady with her husband and kid and I'm like, 'That looks just like a celebrity and I'm trying to think of who, and I'm like, 'Oh, Carrie Underwood?'"

Hamid explained that Witherspoon was wearing a mask and a large cowboy hat so it was hard to identify her but after discovering on Google that Underwood lived in the area, she assumed that it it must be her.

Hamid confronted Witherspoon and asked if she was the "Before He Cheats" singer.

"Hey, oh no, I'm not Carrie Underwood, but have a great day," Witherspoon responded.

Hamid thought she was lying at first but after a moment, she realized that she was actually chatting with Witherspoon.

See the tweets, below.