AE - Workflow "ready for start" for a long time with "Waiting for user input" error

Document ID : KB000105205
Last Modified Date : 16/07/2018
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Workflow don't run with status "ready for start"(Blue) and "Waiting for user input" error in Detail tab. 
Child tasks inside the workflow are waiting for data from user to run.
Choose the option "Request User Input" in job that need user intervention.
Additional Information:
Workflow editor document: