To delete a workspace you need to take a slightly different approach depending on whether you are a single user or if you are tracking time with a team. A single user can simply leave a workspace which results in the deletion of that workspace. On the other hand, if you have been tracking time with a team you need to remove all other users first before you leave and delete a workspace.
Deleting a workspace as a single user
If you are the only user in the workspace currently you can simply leave the workspace which will result in its deletion.
If your Toggl account is connected to multiple workspaces, you need to make sure to switch to the one you wish to leave first by clicking the workspace selector in the bottom left corner of the app:
You can leave any workspace connected to your account from the Team page, by using the 3-dot control at the end of the user row next to your name.
Deleting a workspace with other active members
If you want to delete a workspace with other active members in it you will need to deactivate or delete those members first and then leave the workspace as the only remaining workspace members which will result in it being deleted.
You can find out how to remove users from a workspace HERE. Keep in mind that a user might have an important role in the workspace preventing you from deleting them, such as the "subscribing member" role. Please check out THIS article on how you can resolve that and then proceed with removing all users.