When you create new fields in a table and then go into a form where this table is used, you will not see the new fields in the forms datasource. You could be tempted to go into the properties of the datasource and re-select the table (which would actually add all the new fields).
BUT: Don't do it! You will loose all your modifications and methods made in the datasource !
Better: just exit the Dynamics AX client and enter again. Then, all new fields will appear in your datasource.
vor 1 Woche