When the icon is clicked (while creating a new incident) all possible sub-types should appear under the icon. In order to activate the sub-type, use the configuration utility, (type maintenance module) to set the 2 check boxes – “Include in Event” & “Assignable to Event” by right clicking on the each sub-type.
Include in Event – will display the label for selection
Assignable to Event – will determine whether the user can stop at this level or require that they continue to choose a sub-type of this level.
Also, if the type is assigned to “All Facilities” at a different Type-hierarchy level, it may conflict with setting at another level.