Source: Galactic Historian
When you sleep, you close off your physical Consciousness and open up your Consciousness to the true, Higher dimensional reality.
In other words, when you “go to sleep,” you log-out of the 3D hologram and return to the reality of your SELF to have adventures and communicate with Higher beings,including the Higher expressions of your self.
Since your astral body is fourth dimensional, it only carries you into the fourth dimension.
On the other hand, when your dream adventures carry you into the fifth dimension and beyond, your Consciousness will be wrapped in your Lightbody.
While your consciousness is free of the illusions and dramas of your physical world, it can experience a reality without those limitations.
The Higher the dimension from which you receive your message, the easier it is to forget while you sleep.
This forgetting is because there are more levels of Consciousness through which you must carry your dream back into your waking life. Because you are aware of Higher dimensions while you are awake, you can more easily open the portals into the Higher dimensions while you sleep.