I had this issue a few weeks ago, GM couldn't explain it. This morning I tried to log into 2 seperate accounts and when i log into the second one it tries to kick the primary account saying i have a character logged into world and disconnects it. I play on Cazic thule - Fennin Ro as i have for over 20+ years and only recently has this been happening. Clearly something is wrong and the person responding to my petition before couldn't explain it. I'm not on a true box server so there's no reason unless there's some wonky coding going on
i have had this before. turned out it was the file that save the account info for you launch pad(account names/passwords/etc. some info in the file went bad and no matter what account I was trying to load, it was loading in my main account. can't remember which file it was. but i had to in and delete the file and just remade it.
This happened to me last week. I deleted the one that was messing up and reentered the account information.