If for any reason you woul like to delete your portfolio, then you will need to disconnect all API keys from your portfolio and then you will be able to delete it.
1. Go to your portfolio and press the edit button.
2. Click on the cross icon near every exchange connected to your portfolio to disconnect them.
3. When there is no more connected exchanges left, the "Save Button" will change to "Remove" button. Click the "Remove" button to delete your portfolio.