Welcome to FlyerTalk [MENTION=898894]gpandaleon[/MENTION]!
I suspect that there is a link to make corrections in the "Manage My Application" page of the site. I can't experiment, because I do not have a pending application (a few days ago, I did).
Make sure to allow pop-ups and disable any ad blocking, content-filtering and privacy software/extensions that you may be running in order for the TTP website to properly function and display all your options. I learned that the hard way

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You can always call a Global Entry Enrollment Center for help, but be prepared for long waits for them to answer.
Good luck!