Problem
The requirement is shown as UNCOVERED.
Preliminary check
Is the link direction correctly configured?
Requirement → link: "is tested by" → Xray Test case
Xray Test case → link: "tests" → Requirement
Solution
If the direction is correctly set up, check if the Linked Issues custom field is hidden:
The Linked Issues must be visible. If it is hidden, Jira does not send Xray the link information, and so Xray cannot know that the Requirement is linked with an Xray Test Case.
Make the Linked Issues visible.