Choosing Summoner Name on the Alpha Client

When choosing a summoner name, it says that the name is available but when I click "Yes," it doesn't go through.

I searched through a name checker and it also said that the name was available. OP.gg shows no games, no history, runes, masteries, nothing. Level 1, never played a single game. I'm guessing someone made an account just tohold the name, but it's about a week past its cleanup date.

All of that aside, the purpose of this post is to let you know that

1. Either the 'Alpha Client' (I don't know what you'd call it now, since it's past its alpha stage... beta client?) is indicating that a username is available when it isn't, or
2. There is a problem with picking the name.

It does not have "Riot" or anything else that is prohibited.

Also, I just checked, and the Legacy Client says the username is in use, so one of the clients is indicating the wrong status.