Server Lag

So, I've had this problem for a while now and nothing seems to be fixing it. I'm running on Optifine 1.14.4, and whenever I try to move around my server, it just teleports me back to where I was a few seconds ago. No mobs at all move; chickens just stand there still with their wings flapping. There's about a ten-second delay for me to open chests, furnaces, droppers, etc. I'm completely fine on other servers, but I'm growing tired of this problem. Does anyone know anything that could help?