Whole computer freezing due to using teleport commands in servers: Java.io.IOException: An existing connection was forcibly closed by the remote host.

Whenever I use any sort of teleport commands on any server, my WHOLE computer freezes for about five minutes after, and I am unable to do anything. This error message is produced: Java.io.IOException: An existing connection was forcibly closed by the remote host.

NOTE: No crash logs are ever produced, and nothing is shown in the launcher after it happens. Also happens when I die or a few minutes after teleporting.

I used to have no problem, but this just randomly started happening a while back.