None of our users (including admins) are able to assign issues to users. When we click the assignee field and type in any name, nothing is returned. The project has "any logged in user" permission for "assignable user" as well as "assign issues". When I check the users names from the permission helper, Jira tells me that the users do have permissions (both for assigning and being assigned).
We do have Post-Functions to assign issues automatically to different users for different steps in the workflow. I am wondering if this makes a difference. Although the issues were still assignable to anyone for a few days before this behavior started happening.
(using Jira cloud)