In Salesforce, renaming an existing sandbox is not supported without performing a full Sandbox Refresh. The sandbox name cannot be changed directly through the Salesforce Setup UI or via Salesforce Technical Support from the back-end. A Sandbox Refresh is the only supported method to assign a new name to an existing sandbox.
Renaming a Salesforce sandbox is an expected limitation of the platform. Technical Support does not have a means to rename a sandbox from the back-end — it must be refreshed. A Sandbox Refresh allows you to assign a new name during the refresh process.
To rename a sandbox, initiate a Sandbox Refresh from Setup. During the refresh configuration, you will have the opportunity to provide a new sandbox name.
We encourage you to vote on this functionality on the following post from our IdeaExchange.
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