Edit link results in 404-Page not Found

We use the Q&A plugin on the sub-site priorities.groupsforbernie.org. If I attempt to edit my own questions or answers I get a 404-Page not Found. Permissions are set such that I should be able to do this.

To troubleshoot the issue, I also installed the plugin on a completely different, very basic local install. I had not other plugins running and used twenty-fifteen. I had the same issue there.