I Can't Join Online Servers!

Minecraft Windows 10 Edition won't let me join online servers because my name has a space in it! Since Minecraft Windows 10 Edition is connected to Microsoft, when you go to settings you can see you name BUT... you can not change it cause it's connected to Microsoft. to change your name it cost cash that I don't have. This bug has been bugging me for a while, please give me a solution`