To automatically add your team ID to a dropdown list in the Team field of the General section, follow these steps:

1. Open Xcode and go to Preferences > Accounts.
2. Add your Apple ID in Accounts.
3. Open your 4D for iOS project in Xcode.
4. In Signing & Capabilities tab, select your Team from the dropdown list.

After you reopen the mobile project, in the General section you should be able to select your team ID from a dropdown list in the Team field.