This issue is due to the fact that you must be an editor or higher user with user privileges to launch a manual workflow.
However, if you have a viewer that has the ability to launch a manual workflow, or a user right like a viewer / uploader, the problem will be cleared.
I also can't grant permissions well because of this, and I can't use the manual workflow.
Request the implementation of user privileges below the editor privileges that can launch the workflow.
This issue is due to the fact that you must be an editor or higher user with user privileges to launch a manual workflow.
However, if you have a viewer that has the ability to launch a manual workflow, or a user right like a viewer / uploader, the problem will be cleared.
I also can't grant permissions well because of this, and I can't use the manual workflow.
Request the implementation of user privileges below the editor privileges that can launch the workflow.