No results found for simple index

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4

@databrecht
From the GQL Relations example I have:

{
"ref": Ref(Collection("Todo"), "287753950702076424"),
"ts": 1610682678290000,
"data": {
"title": "Build an awesome app!",
"completed": true,
"list": Ref(Collection("List"), "287753820121858572")
}
}

in the ToDo collection and

{
  "ref": Ref(Collection("List"), "287753820121858572"),
  "ts": 1610682277730000,
  "data": {
    "title": "Development"
  }
}

in the List collection.
I checked the field spellings this time.
The tutorial schema auto creates an Index: list_todos_by_list
However, if I search for list by ref “287753820121858572” I get:

No results found for the index "list_todos_by_list"

It is possible this is related to internal server error
which is currently unresolved and may be impacting indexes such as this one(?).
If that is not possible, why is the ref unable to find the document in the specified list?
Thanks …