Hello dear Fellas of the PBE Community,
as everyone can see, multiple Accounts got the access to the Launcher denied.
For giving others more information to this, please share your Screenshots of your Ban or Error Messages in the Comments.
I don't know if it will help the affected ones, but I would then share this Thread to the @RiotSupport 's Twitter to have a clear look into it.
People wrote in the Description, that they didn't do anything that could violate our PBE Rules or general League of Legends Rules, so it could be probably a Bug.
_From the Unofficial PBE Discord_
Account locked: Chinese location/account
It seems that PBE accounts belonging to Chinese people/residents of China got locked for some reason. The specifics are unknown to us.
Riot is aware of the situation and looking into it.
if this applies to you, then riot will find a fix, if not, then it was probably because there were 2+ IPs on the account (someone hacked it for example) which can get accounts closed/disabled/banned
_Thanks to Bernadetta for posting it!_