Are you trying to connect as one of your other users or your master user?
The reason I ask is the ‘forbidden char/command over ssh’. bash, echo and export aren’t in the limited shell command list.
If it’s your master user then it’s probably time to look at some server logs.
If its your other users then edit /etc/lshell.conf and add those commands to the allowed list:
[global]
logpath : /var/log/lshell/
loglevel : 2
[default]
allowed : ['grep','cd','cp','-d','-dmS','git','irssi','ll','ls','-m','mkdir','mv','nano','pwd','-R','rm','rtorrent','rsync','- S','scp','screen','tar','unrar','unzip','nano','wget']
forbidden : [';', '&', '|','`','>','<', '$(', '${','sudo','vi','vim','./']
warning_counter : 2
aliases : {'ls':'ls --color=auto','ll':'ls -l'}
intro : "== Seedbox Shell ==\nWelcome To Your QuickBox Seedbox Shell\nType '?' to get the list of allowed commands"
home_path : '/home/%u'
env_path : ':/usr/local/bin:/usr/sbin'
allowed_cmd_path: ['/home/']
scp : 1
sftp : 0
overssh : ['ls','rsync','scp']