The game lags so much and it happens only when I add a server

Don't know i did some research couldn't find it there is only one thing they say mods and i Don't have any mods

When i hit play the game lags so much and it happens only when i add a server here's the ip

Sahilsharmahatl.aternos.md 

Port

26838

And then i add it it says in correct ip adress and im pretty sure it was right

And then the game froze and i exited and the only way to fix it is by reinstall it pls fix