Can't join a 1.13 server.

I'm trying to play a survival 1.13 world with my friend, but every time I try to join it gets stuck on "Loading terrain...", and then sometimes afterwards flashes the world and turns gray, then disconnects with this message: "Internal Exceotion: java.IOException: An existing connecting was forcibly closed by the remote host", I'm not sure what the problem is or how to fix it, but I know that it worked for me with1.13pre10