Insomnia is a common sleeping disorder that can't make you fall asleep. There can be many causes of the disorder but it has a wide variety of Impacts on day-to-day life. For example, a person cannot even drive or watch TV properly. It can't sleep during the night but causes huge lethargy during the day.
https://www.resmed.com/in/en/consumer/insomnia-symptoms-causes-consultation.html