500 Error, And Realms Not Saying I Own It

When I sign onto my account and go to the Realms tab, it tells me that I need to buy Realms even though I already have a Realms and it still has a few days left on it. When I sign into my second account to see if I can log on through there, the Realms appears, but when I try and log on to it, I get the 500 error. I have tried to restart my computer and the minecraft client, but nothing is working.