Objects remaining in viewport

The object has been placed within the viewport dotted line.

All placed in the same layout.

Some of the objects are fixed.

Other objects are not pinned.

Disappears when moved.

How do I fix it to a viewport?

Didn't understand when you said "Disappears when moved"

Moved? what moved, the object? the viewport using Scroll-to behavior?

Anyway, you can do one of these things if you want something to always remain in the same place on the Viewport (dotted rectangle):

1. Keep the things on a separate Layer that has 0% Scaling, and 0% Parallax X and Y.
OR,
2. Use 'Anchor' behavior to that object. Particularly useful when you're having fixed objects on the sides or corners of the screen.

English is not my native language.

Sorry..

I'm talking about HUD.

It's the same Layer.

Some things follow the player.

Some objects are secured to the upper left corner.

Don't use pin behavior to pin something on your screen, use Anchor Behavior for that