Call forwarding won’t disable on iPhone 12 Pro Max

Hey there Itsaboutmyapple,

Thanks for reaching out to the Apple Support Communities. To get started, since you've confirmed that Call Forwarding has been disabled in Settings > Phone on your device, you may need to reach out to your carrier to ensure that the feature is not also enabled on their end.

For more details, check out this link here: Set up call forwarding and call waiting on iPhone - Apple Support

For information about conditional call forwarding (if available from your carrier) when the line is busy or not in service, contact your carrier for setup information.

We hope that's able to help.

Take care!