Hole in Floor error

Hi, Im on my server and i cant get into the end, i can access the nether and the default world, but not the End. I used a portal to get to the end but it was just The End with no land and no ender dragon. I deleted the World_End but it didnt work, please help. Also some of the players are saying they could get in but there were hundreds of ender dragons, please help.
Thanks
P.S. THIS IS ONLY FOR THE END