Requisition workflow submission and approval
Hy Kumar,
within the PR Workflow there is a task for "Review purchase requisition", this is used to qualify and review the content of the PR.
You just need to add this task as the first task within the Workflow and assign it the the system admin.
So the original requester can submit the PR and it will be assiged first to the Sysadmin to review in that first step. The the Sysadmin can approve and forward to the next WF task (may be for approval) or he can reject to the submitter.
Hope this helps.
Herzliche Grüße / kind regards,
Andreas Raithel
D365FO Solution Architect