Creating new balloon scene and script results in Error: 'Class "DialogueResource" hides a global script class.'

[CharonEXE]

Godot
v4.4

Dialogue Manager
v3.5.1

Issues:
I was following exact steps on this video by @nathanhoad

But when it reaches timestamp 3:12, where after creates a new balloon scene with portrait, my run always ends with this error.
Class "DialogueResource" hides a global script class.
I saw someone report the exact same issue a year ago here, but the issue is closed without any clear solution being mentioned.

I surf online and found this post saying that

This happens when you add a script as a child node (Command+A on Mac, “Plus/Cross Icon” under Scene) instead of instantiating a scene (Shift+Command+A on Mac, “Chain Icon” under Scene).

Also here says that

...you really need to rename your file with only upper or lower case modifications, ...

But still, nothing found really directly helps as even I removed my own created balloon, the issue persists. Not mentioned that I have no clue what to rename if the solution is applicable.

From what I can gather here is that it seems to be that the steps in the video mentioned earlier, which create a new balloon thru Project > Tools > Create copy of dialogue example balloon... will always bring to this issue. I am seeking for a solution so that I can proceed with my development.