Nether Times Me Out

I have a better mc modpack server that i play with my friend, but whenever i enter the nether, its just a void where i keep dropping down till about y -2700 ish, where i get the error "timed out" and i need to restart the server, where its rolledback about 10 minutes. I tried to go into creative mode and fly at y 30 but it timed me out after about a minute to two. Nether is allowed, and i dont know what the issue could be.