Using Page Composer to remove delete button

Content

In the UI I'd like to remove the 'delete' button from Personal Contributions. I found some guidance on here that advised to open a Sandbox and use Page Composer. I've done that and accessed the 'panel section edit', where I believe I need to make the delete button un-rendered. Assume this would be done by unticking the check box against Delete Rendered, but it's greyed out (see attached screenshot). Not sure if there's another way, or if I've gone wrong somewhere. Does anyone have advice?

Thanks

Leanne

Version

20D (11.13.20.10.0)