Statechart Checks : (C2047) The tested chart is a definition chart with multiple top-level boxes

(C2047) The tested chart is a definition chart with multiple top-level boxes

The tested chart is used as an off-page definition of an instance state and has multiple top-level states.
Error In:
Completeness
Example:
In the following figure, the off-page chart B erroneously has more than one top level box (C and D).
Erroneous Elements:
The tested chart