Grace VanderWaal Charlie Puth
Charlie Puth invited Grace VanderWaal for a collaboration. YouTube/Tonight Show starring Jimmy Fallon

After making fun of Grace VanderWaal for not knowing the popular American boy band NSYNC, Charlie Puth invited the “America’s Got Talent” winner to write a song together.

The 24-year-old “See You Again” hit maker raised the possibility of a collaboration with the Ukulele-playing singer-songwriter after she appeared as a guest on The Tonight Show Starring Jimmy Fallon.

In the episode aired last week, VanderWaal and Fallon played a singing version of the Chubby Bunny Challenge, wherein one tries to sing with a mouthful of marshmallows while the other tries to guess the song’s title.

Fallon was mimicking the NSYNC’s signature moves for the boy band’s 2000 hit single “Bye Bye Bye,” but the 12-year-old remained clueless as to the song’s title.

“Bye Bye Bye, what?” she said, apparently ignorant to the song’s existence or even the boy band’s.

For his part, Fallon made a face palm and admitted “I am so old.”

Reacting on the funny episode, Puth reached out to VanderWaal on Twitter, and said “Hey @GraceVanderWaal you don’t know the song ‘Bye Bye Bye’ by NSYNC?”

Then Puth congratulated VanderWaal for her winning the NBC’s top-rated talent show.

“You are just so unbelievably talented. Congrats on everything. Let’s write a song,” he tweeted.

“That would be so unbelievable. Just say when and I will be there,” replied Vanderwall, who was known for performing four of her original songs on “America’s Got Talent” season 11.

After winning the talent search on Sep. 11 and bringing home the US$1 million (AU$1.3 million) prize, VanderWaal signed a record deal with Simon Cowell’s Sysco Music, which operates under Sony’s Columbia Records. During the competition, Cowell predicted VanderWaal to be the next Taylor Swift, who is an accomplished singer-songwriter herself.

VanderWaal also got the attention of other famous music artists, including Taylor Swift, Katy Perry and Lady Gaga. Apart from Jimmy Fallon’s Tonight Show, VanderWaal also appeared on the Ellen DeGeneres show. (Read: Taylor Swift, Katy Perry et al. cheer on ‘America’s Got Talent’ winner Grace Vanderwaal)

Audition for “America’s Got Talent” season 12 is currently ongoing online. NBC has announced cities for its open call auditions. (Read: America’s Got Talent’ Season 12 audition dates announced)

WATCH: Grace VanderWaal on Tonight Show starring Jimmy Fallon