Hello Anirban Basu,
This is not possible to comment anything if there is any change made or not in the workflow configuration which you have asked. May be your partner vendor shall put some light on this.
However; there could be multiple reasons involved which may lead not to create the work item.
Is this the first case you have faced? Did you submit any PO before? If yes; then what is the approval status on those documents?
You may check in below areas if you have appropriate roles assigned to you to access certain module and forms in D365. Else; you may check with any other user who is atleast having "System admin" role assigned to check below areas.
--- Go to System administration > Setup > batch group.

Make sure that for all the batch groups whatever you created in this form; batch servers must be available in the Selected servers section.
In above example; we have batch groups like 'Blank', 'Email' and 'Workflow'. You have to check in every batch group and push all batch servers from the "Remaining servers" section to "Selected servers" section.

2) Go to System administration > Workflow > Workflow infrastructure configuration.
Make sure you have selected appropriate batch group as shown below.

3) Go to System administration > Inquiry > Batch jobs.
In this form; workflow related batch jobs are set with "Waiting" status. And the recurrence of these batch jobs are set to "No End Date" so that these jobs should always run.


In addition; you can check the following to avoid any work item not creation related issues in future.
1) Make sure the person who is the approver; "Person" is linked with this user in the Users form. To access this form; go to System administrator > Users > Users.
2) User should have required roles and privileges assigned to approve the workflow.
3) Make sure the approver is assigned in the workflow configuration form if this is user based.
4) If the workflow you designed is "Participant" based; make sure this is appropriately setup in workflow configuration.
Kindly review and update us in this forum.
Best regards,
Sourav Dam
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