“Tighten capsule” will display on Nima when the capsule top does not appear to be fully closed. If you see this error, remove the capsule and try to further tighten the cap. The green ring should not be visible and the top of the capsule should be flush with the body.
Once the cap is closed and aligned, re-insert the capsule and try to run the test again.
If you are having trouble closing the capsule cap, please reach out to firstname.lastname@example.org so we can send you a capsule wrench!