When angels sinned, God did not let them go free without punishment. He sent them to hell. He put those angels in caves of darkness, where they are being held until the time when God will judge them.
And remember the angels who lost their authority to rule. They left their proper home. So the Lord has kept them in darkness, bound with everlasting chains, to be judged on the great day.
Then I saw another powerful angel coming down from heaven. The angel was dressed in a cloud. He had a rainbow around his head. The angel’s face was like the sun, and his legs were like poles of fire.
Then the angel threw the dragon into the bottomless pit and closed it. The angel locked it over the dragon. The angel did this so that the dragon could not trick the people of the earth until the 1000 years were ended. After 1000 years the dragon must be made free for a short time.