I have tried everything but I am only able to stay in the realm for a few seconds before I get the error message that the existing connection has been forcibly closed by the host.

I have been playing in my realm for almost a month and yesterday when I was playing I got the error message that my existing connection was forcibly closed by the host. I tried to rejoin a few times but I kept getting the same message. Assuming it was a problem with my laptop I restarted it, updated it, and continued to look for possible solutions. After spending an hour or two I have come up with nothing. Now I can only enter the realm for a few seconds before I am kicked with the same error message.