This message appears when the age registered to the game account you are trying to link does not match the age registered to your SEGA Account.
Please check that the registration information for both your game account and your SEGA Account is correct.
You can confirm the date of birth registered to your SEGA Account by logging in to the SEGA Account official website and opening “Account Settings.”
After logging in, select “Account Settings” from the menu in the top-right corner.
Please note that this support desk can only assist with inquiries related to SEGA Accounts and SEGA Account campaign sites.
For questions regarding game accounts, please refer to the game's FAQ or contact the game's support desk.