It is not easy to sleep well in space
Let us start by stating that space is not a very hospital environment for humans. If you survive the trip to the station, then the zero gravity and the large amounts of radiation you will be exposed to can be enough to cause permanent changes in your body. Astronauts cannot even sleep well in peace.
That is because sleeping in zero-g is very different. Astronauts need to strap themselves into a sleeping bag, so they do not float off. In addition, space stations are noisy environments, and if they reach higher altitudes, many crewmembers report seeing flashes of cosmic rays, which woke them up.