To speed up user operations with linked Jira items, Zephyr stores some Jira data like field values in a cache.
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Log in to Zephyr Enterprise as an administrator.
Go to the Administration > Defect Admin settings. Then go to Jira Management > Jira Custom Fields Management tab.
Select Clear All and he click Clear Cache:
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You can also clear cache data of individual projects, item types or items, but we’d recommend clearing the entire cache.