Hi moelshimy,
Are you using the dynamics 365 UCI?
If so, the ‘Run workflow’ button not show in the bar directly like in the old Web Interface.
1.In fact, ‘Run workflow’ button has moved under ‘Flow’ button in UCI.
So if you have an on-demand workflow configured for the entity that is being looked at then the Run Workflow options appear under the Flow fly-out button.

Note: if there are no on-demand workflows configured for the entity then the Run Workflow options will not appear under the Flow fly-out button.

You can go Settings > Process to check if this entity you need has created an on-demand workflow.
2.Also, you need give the user enough privileges in security role.
Go Settings > Security > Security Roles to open one that the user has assigned.
(1)’Run Flows’.
If it is not checked, flow button will be not shown in the bar.

(2)’Process’ Read privilege.

Regards,
Leah Ju
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