Once again @Ben.Young is on the right track. Here’s a bit more info on what’s happening behind the scenes:
While a form is technically called a “form view”, the form that you see outside of Airtable has almost no connection to the actual Airtable data. As Ben demonstrated, you can see the contents of linked records (to a certain extent), but even there it’s not a live look at the data. If someone were to add a record while that form was open, it wouldn’t appear in the list of linked records because that list was collected at the point when the form was opened. In short, the few things that you can see within a form view are effectively a snapshot of the data from the time that the form was opened.
In a similar vein, data that you enter in a form has no effect on what’s happening in the table until you submit the form. The form is effectively isolated from the table. This is good because it provides a simple level of security so that changes in the form don’t immediately do things like trigger automations, but that isolation can have its downsides as well, as mentioned above. If you want a more robust form for your users, you’ll need to look into third-party form solutions and/or tools that do more than just present a data snapshot to users.