You can create more than one codespace per repository or even per branch. However, each user account has a limit of 10 codespaces. If you've reached the limit and want to create a new codespace, you must delete a codespace first.
Note: Only the person who created a codespace can delete it. There is currently no way for organization owners to delete codespaces created within their organization.
Navigate to the "Your Codespaces" page at github.com/codespaces.
To the right of the codespace you want to delete, click , then click Delete
For information on deleting a codespace in Visual Studio Code, see "Using Codespaces in Visual Studio Code."