Please check your Metamask...
Names must follow these rules:
-Must be unique
-32 Characters or Less
-A-Z (lowercase)
-Name cannot be just numbers, but numbers are allowed
-No special characters
-No more than one space between characters
If the transaction fails, one of these criteria was not met properly.
Names are yours permanently (for vanity URLS). But only your most recent name will show up on the leaderboard/game UI. You can own as many names as you'd like.
Make it good.
The fee is distributed across community members who made this game possible.