AJAX Error on Add Node form via Comments

An AJAX HTTP error occurred.
HTTP Result Code: 500
Debugging information follows.
Path: /portal/system/ajax
StatusText: Service unavailable (with message)
ResponseText: EntityMalformedException: Missing bundle property on entity of type node. in entity_extract_ids() (line 7766 of C:\xampp\htdocs\portal\includes\common.inc).

I have Inline Entity Form - Multiple field made editable via Comment Alter, in a certain content type. When I use ADD NEW NODE, the error happens.

As workaround, make the reference by editing the content itself, inside the form. Once added it already appears as an item in the comment display. Add to this, the new node is editable in the Comment display.

What we want is we can add entity references, inline form through comments. But this error persist.

Thanks in advanced!

Additional: Add Existing Node works fine btw