Realms in Java are extremely laggy

When I am playing on my realm with my friends and even when I am playing on my own on the realm, there are all sorts of lag related problems. The blocks don't place, the mined blocks don't get mined, the mobs freeze, and then suddenly are all on me a second later. I've died at least twice because of the lag, and I have to disconnect and reconnect from the realm often. I would assume that the resetting would help make it less laggy, but often it has no effect. Please fix this issue, it makes me not want to play Minecraft with my friends, and that sucks.