In backend content field is not restricted to use HTML editor for content field. This is default field for post content and it available for all post types. If HTML added by admin then it will display it HTML tags at front-end.
Thank you Kiran, it´s not working, that´s the problem. I can see it, but changes are not made as shown in the images I sent. Once I publish or update the listing all changes made in html are not saved.
To open a new support ticket, first select the relevant forum and then click the "New Post" button. Example: You need support for the core plugin? Click on Core Plugin support and click on the "New Post" Button.