I have Imported employee time file with approval status as "PENDING". If it is "pending" workflow is not triggering to Manager or I cannot see workflow requesting pending under employee manager. You can check the employee's managers and proxy and check the to-do list for workflow request is not available.
Imported requests all have status Approved in the target system.
The import process does not trigger a workflow, so don't make any entry in the Status field of the import file.
Please refer to page 47 "Note" at the end of section Admin Center Settings->Setting Up Employees for Time Off-> Importing Leave Requests, of Q3 2017 EC Time off Implementation handbook.
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Trigger workflow when importing leave request workflow not triggered importing employee time with status pending , KBA , LOD-SF-EC-TIM , Time-Off , Problem