I'm using Joomshaper Helix Ultimate as a template. Also have SP Page Builder Pro installed. Had to set x-frame options to sameorigin to see the preview page in the frontend editor (through the frontend and backend), but can't get the icons (you would normally see them in the blue or green areas top left of boxes in image) and the content in the inner box should show text. Images and some other items are visible.
I used that combination (Helix and page builder) in the past and I had no issues. Can you send me administrative credentials and also the steps to reproduce the issue? If so please use the email from which you receive forum notifications.