In order to join TikTok Creator Marketplace, you’ll first need to verify your age on TikTok.
To confirm your age on TikTok, please contact the app’s customer support and request a date of birth update.
Here’s how to do it from the mobile app:
Login to your TikTok account on the TikTok App
Click Profile, then select the hamburger icon in the top right
Click Report a problem > Account and Profile > Editing Profile > Other
Click Need More Help and type in your request (e.g. “I would like to request to update my date of birth.”), then click Report
You will receive an email requesting a copy of your photo ID to confirm your date of birth. You must submit one to complete this process.
For more information, please see this article here.