Hello @amone,
Thanks for writing in!
Please check your pretty permalink in Settings > Permalinks.
You may also need to go to Cornerstone > Settings > Permissions > Portfolio. Make sure that it is enabled so you can edit it.
And if you are trying in edit the Portfolio archive, you may need to create a custom archive layout via the Layout Builder which is available in the Pro theme only.
We would love to check your site by the way. You can create a secure note in your next reply with the following info:
– Link to your site
– WP login URL
– WP username
– WP password
– WP Administrator Role
– Confirmation that we can access and make changes to your site
To know how to create a secure note, please check this out: How The Forum Works

Best Regards.