Are you using Cloud or Server? For Cloud you would have to sign up for a new instance and migrate from your old one to the new one per this KB, https://confluence.atlassian.com/cloudkb/changing-the-cloud-instance-url-address-or-migrating-to-a-new-cloud-instance-691011835.html
If you're using Jira Server, it's possible you would not see this in the system admin menu if you were just a Jira Admin and not a System Admin. Managing global permissions explains that this is expected as only System Admins can edit this system setting.
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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