3061329 - Multi Project Monitor: ASSERTION_FAILED dump raised for /IWBEP/CL_V4_MED_MODEL_FACTORY

When calling the 'Multi-Projectmonitor' (UI5-based technology) from Fiori Launchpad a dump occurs:
ASSERTION_FAILED     /IWBEP/CL_V4_MED_MODEL_FACTORYCP ...

Within transaction ST22, it can be seen that the reason is ASSERTION_FAILED on variable ls_model_data in method /IWBEP/CL_V4_MED_MODEL_FACTORY->CREATE_MODEL_INTERNAL.

Short Text                                                                                        
    The ASSERT condition was violated.   

Information on where terminated                                                                   
    The termination occurred in ABAP program or include                                           
     "/IWBEP/CL_V4_MED_MODEL_FACTORYCP", in "CREATE_MODEL_INTERNAL". The                          
    main program was "SAPMHTTP".                                                                  
                                                                                                  
    In the source code, the termination point is in line 185 of  program or                       
    include "/IWBEP/CL_V4_MED_MODEL_FACTORYCM00A".       

*   Return cached model                                                                     
>>>>>    ASSERT ls_model_data IS NOT INITIAL.   

SAP Fiori for SAP Portfolio and Project Management (PPM-FIO) 
SAP Fiori for SAP Portfolio and Project Management for SAP S/4HA (PPM-FIO) 

ASSERTION_FAILED, /IWBEP/CL_V4_MED_MODEL_FACTORYCP" bzw. /IWBEP/CL_V4_MED_MODEL_FACTORYCM00A, CREATE_MODEL_INTERNAL, Multi-Projekt-Monitor, MPMon, switch area 0006 - name 0069 , KBA , PPM-PRO , Project Management , PPM-PFM , Portfolio Management , Problem