Do you match the rules for the security level you want to set it to, and do you have "edit issues" and "set security" permission? (Note that admin means admin, not "can do all sorts of non-admin things", as that's a terrible access model and one JIRA sensibly avoids)
The Closed status might have a property that forbids editing the issue.
After following these steps, you should be able to edit the issue.
Hey Community mates! Claire here from the Software Product Marketing team. We all know software development changes rapidly, and it's often tough to keep up. But from our research, we've found the h...
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