If the "Set mandatory modifiers later" option is enabled, the dish (menu item) is added to the order first, and mandatory modifiers can be entered later, i.e. the dialog mode for adding a dish (menu item) with modifiers to the order is enabled.

To make sure that the modifier scheme opens automatically when adding a menu item to an order, set the Lower Limit in the modifier scheme for this group to 1 (or more).
If you set the Upper Limit, then when it is reached at the cash register, the automatic transition to the next group of modifiers (or the “Common modifiers” group) will occur.