"Internal Error" When Using a Character Boost

Recently come back and bought Epic Edition
Got following problems:

  1. “Internal Error” When Using a Character Boost
  2. Couldn’t joint any guild, keep showing up "Couldn’t create an application for the posting.’
  3. Mail system stucked, showing new mail in the mailbox, but nothing appears

Any help much appreciate

having same internal error for character boost

did you manage to fix it?