From the above description, it is not easy to understand what exactly you did.
Generally, adding a field to a data structure is not enough to make it appear on screen (in any Tersus application, including a mobile app). The additional field enables you to store another piece of data, but you still have to take care of displaying the data on screen (and, assuming you also want to store data records in the database, you also need to take care of database update).
For example, if you look at Stage 4 of the Guestbook tutorial, you can see that for each field in the Visitor database record, there is a corresponding display element in the New Visitor form, and to save a record in the database, the content of the display element is copied to the relevant database field (in Create Record).
I am not sure this addresses your problem. If not, please export your project as David suggested and attach it to your answer. If for any reason you are reluctant to share it through the forum, you can mail it through Contact Us.
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