Did you try moving & touching stuff while flying far away?
The thing about flying very far is that you're probably in the same fixed Superman position, not really moving your dream body anymore. If you don't move, your consciousness shifts awareness towards your physical body and you wake up. Try it next time: just stop & don't move, don't do anything, you're likely to wake up.
So doing the opposite, moving your dream body a lot & touching dream stuffs, tends to prolong your dream. That's why teleportation works better for moving to different areas.
Funny enough, not moving your body is also how your consciousness shifts and enters the dream state when awake.
The thing about flying very far is that you're probably in the same fixed Superman position, not really moving your dream body anymore. If you don't move, your consciousness shifts awareness towards your physical body and you wake up. Try it next time: just stop & don't move, don't do anything, you're likely to wake up.
So doing the opposite, moving your dream body a lot & touching dream stuffs, tends to prolong your dream. That's why teleportation works better for moving to different areas.
Funny enough, not moving your body is also how your consciousness shifts and enters the dream state when awake.