Olivia Rodrigo has revealed she was once interrogated by police officers at the U.S. border due to a case of mistaken identity.

The Good 4 U singer was crossing the border after performing her Guts World Tour shows in Canada when cops called her in for questioning in the middle of the night.

I got in trouble with the law for the first time in my life. So we were going from Canada to like Portland or something. We were at border control," she recalled on The Tonight Show Starring Jimmy Fallon on Tuesday. "I give them my passport... and they knock on the door and they're like, 'We need Olivia.'"

Olivia, 21, stepped out of her tour bus "delirious" at 3am thinking they simply wanted an autograph, but she ended up being escorted into an interrogation room.

"He's like, 'Have you ever been arrested?' I'm like, 'No, I haven't been arrested.' And he's like, 'Are you sure?'" she continued, admitting she started to second-guess herself. "I'm like, 'Oh my God, maybe I was arrested and I didn't know it.' He scares me, he's like, 'You know, you could go to jail for lying to a federal officer like this. Like, this is really bad.' I'm freaking out. I'm like, 'I'm not gonna be let into America!' I'm so scared. I'm, like, having a panic attack."

After enduring 30 minutes of interrogation, the officer realised they had confused Olivia with a felon who had a similar name.

"He looks at me and goes, 'What's your name?' and I go, 'Olivia Rodrigo. R-O-D-R-I-G-O' and he's like, 'Oh, there's a girl that looks just like you, that's your same age and has been arrested multiple times. Her name is Olivia Rodríguez,'" the Vampire singer remembered. "I was p**sed! You didn't look at the name on the thing and you're interrogating me for 30 minutes?! But phew, crisis averted."

Olivia's Guts World Tour began in February and wrapped earlier this month. A concert film was released on Netflix on Tuesday.

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