Hi Shan,
Your request was not activated. Have you tried to activate or check your process chain load, may be stucked at dso actvation before. if stcuked there, continue by using prorgam RSPC_PROCESS_FINISH and get requried inputs from table - RSPCPROCESSLOG. if your search you will get in scn.
or You can activate manually at DSO , request tab, select first request and click activate icon, pop comes, select request and click on start. it starts activation.
Thanks