How can I set a role user to Unassigned?

[J]

I was able to set up roles for various projects and assign the default member of a couple roles to Unassigned. I tried to do this again today and the user picker will not allow me to do so. It says there are no matches.

I have checked the configuration and it is set to allow unassigned issues. We do have many unassigned issues. I am able to manually select Unassigned as an assignee.

I'm not sure what I'm missing. I am fairly new to JIRA and I don't know how to script. If I'm missing other important info please let me know.

Thanks!

[J]

More info that might help you help me:

- I have the workflow set up to auto-assign based on roles for certain transitions. While trying to figure out why I could no longer set a role user to Unassigned I deleted Unassigned as a role user in some places and now my workflow is broken.

- We are using JIRA (v5.2.7#850-sha1:b2af0c8)

- we have this plugin to help with post functions. https://marketplace.atlassian.com/plugins/com.innovalog.jmwe.jira-misc-workflow-extensions

- The error I get is :

The actor: 'unassigned' is not active. Therefore, it is not possible to add it to the project role: '10050'