You can update your personal data in the app via Card > Settings wheel > Personal Information, including:
Registered address, as it appears on your ID
Street and house number
Zip code
City
State
Country
Employment status
Email
Tax Identification number
Phone number
To change your Tax Identification number, go to Settings wheel > Tax ID.
The details linked to your card can be different from your Grover account. Make sure you're in the Card section of the Grover app when updating your information.