Can't play on whitelisted pocket realms servers

I am whitelisted to 3 realms multiplayer servers, and cannot play on any of them. They all have the 'green light', but when I try to go into one, I am either kicked out immediately with a "Could not connect to server" or stuck on a screen that says "Connecting to realms" with a spinning icon. I have tried waiting for over 10 minutes and nothing happens. I am sure it is not my connection. I have tried resetting my ipod.