I actually just got this issue.
I tried to touch up my character's bio but everything I typed just turned into "~". I logged out and tried to log back in, but my account wouldn't let me back in. So I came to the forums to make search for someone who had this same issue, but when I typed my text came out in Thai.
It took me a moment to realize my computer suddenly changed from English to Thai.
I switched back to English, logged in, and successfully got into the game and can now type.
Perhaps your computer did something similar?