3396817 - The ASSERT condition was violated while Mass Update

Dump below happens while MASS/XD99/XK99 is used to update customer/vendor information.

Category               ABAP programming error
Runtime Errors         ASSERTION_FAILED
ABAP Program           CVI_KA_BP_VENDOR==============CP
Application Component  AP-MD-BF-SYN

 Short Text
     The ASSERT condition was violated.

 What happened?
     The current application program has detected a situation with the
     ASSERT statement that should not occur.
     The reason for this runtime error was one of the following:
     - For the checkpoint group specified with the ASSERT statement, the
     activation mode is "abort".
     - A system variant has been used to set the activation mode to "abort"
     globally for all checkpoint groups in this system.
     - The activation mode is set to "abort" at program level.
     - The ASSERT statement is not assigned to any checkpoint groups.

Information on where terminated
    The termination occurred in ABAP program or include
     "CVI_KA_BP_VENDOR==============CP", in "GET_T077K_LINE". The
    main program was "SAPMMSDL".

    In the source code, the termination point is in line 3 of include
     "CVI_KA_BP_VENDOR==============CM00B".
    include "CVI_KA_BP_VENDOR==============CM00B".

Source Code Extract

Line  Code

    1 method get_t077k_line.
    2
>>>>>   assert i_account_group is not initial.
    4
    5   select single * from t077k into r_t077k
    6     where ktokk = i_account_group.
    7
    8 endmethod.

SAP S/4HANA

KBA , LO-MD-BP-VM , Vendor Master , Problem