3471627 - Dump ASSIGN_ILLEGAL_COMPONENT during settlement run

Below dump is raised when settlement run is executed for condition contracts 

Category               ABAP programming error
Runtime Errors         ASSIGN_ILLEGAL_COMPONENT
Except.                CX_SY_ASSIGN_ILLEGAL_COMPONENT
ABAP: Program          CL_WB2_BVB_SERVICES===========CP
Application Component  LO-GT-CHB

 An exception has occurred in class "CX_SY_ASSIGN_ILLEGAL_COMPONENT". This exception was not caught
 in procedure "ADJUST_SIGN_CHANGE_SIGNS" "(METHOD)" or propagated by a RAISING clause.
 Since the caller of the procedure could not have anticipated this exception, the current program was terminated. The reason for the exception occurring was:
 The reason for the exception is:
 The component with name "VBTYP" or number "-1" either does not exist or was not assigned at runtime.

 This can occur in the following cases:

 - A dynamic expression was specified that references this component, such as REF->(DYN) or STRUC-(DYN).

 - An ASSIGN statement attempted to access this component and to assign a field symbol to it.

Condition contract management

Settlement management

dump , VBTYP , N , cl_wb2_rebates_con=>gc_adjust_sign-sd , ADJUST_SIGN_CHANGE_SIGNS , CL_WB2_BVB_SERVICES  , KBA , LO-GT-CHB , Condition Contract Maintenance , LO-GT-CCS , Condition Contract Settlement , LO-AB , Settlement Management , Problem