Hi, this an an issue that can not be resolved through the Apple Support Communities. You will need to communicate with the Goldman Sachs support team and probably the Apple Support team.
Apple Card accounts are associated with Apple IDs. This can’t be changed or modified.
The solution may involve permanently closing the existing account and applying for a new account with the correct/proper Apple ID and then inviting the new co-owner.
Another option would be closing the existing account and then each person applying for their own account. Once each account is approved, they can apply to have their accounts merged into an account with a combined credit limit.
CONTACTING — Goldman Sachs Bank
• Using Messages; chat with an Apple Card specialist
• Calling us toll-free at 877-255-5923; or
• Writing to us at Lockbox 6112, P.O. Box 7247, Philadelphia, PA 19170-6112.
Apple Support Team,
1-800-MY-APPLE
I hope this helps.