Minecraft realms will not work

I got realms so i could move my world from my computer to my xbox and the realm wont let me. Then I tried unistalling and installing minecraft and i lost my world. Please tell me why I should pay 7.99 for a realm that say i can tranfer worlds between platforms when it doesn't work. My world is gone along with its progress. I wasted time, money, and a world that my friends and i worked hard on.