You can get to the right permission scheme via the project header -> permissions or by going into the administration section and finding the list of schemes and clicking on the one your project is associated with.
You can run the permission helper in order to understand why it's not possible to assign tickets to this particular user. Please follow the documentation below:
Connect with like-minded Atlassian users at free events near you!Find a group
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no AUG chapters near you at the moment.Start an AUG
We're bringing product updates and pro tips on teamwork to ten cities around the world.Save your spot