Hello. I've been getting this issue when just exploring my minecraft server. I dont do anything to make this trigger but I may have a suspicion that its my WiFi. After a couple of hours of researching ...

Changing priority for Java and Minecraft launcher, Wiping DNS cache, When server works: When we're in the same phisical LAN, next to us each other, BUT not by server files. Only by singleplayer "Open ...