(help) console crash

Error running system event handling function for resource essentialmode: citizen:/scripting/lua/scheduler.lua:41: Failed to execute thread: @essentialmode/server/main.lua:13: attempt to concatenate a nil value (local ‘rText’)
stack traceback:
@essentialmode/server/main.lua:13: in local ‘userCallback’
citizen:/scripting/lua/scheduler.lua:320: in upvalue ‘handler’
citizen:/scripting/lua/scheduler.lua:219: in function citizen:/scripting/lua/scheduler.lua:218
stack traceback:
[C]: in function ‘error’
citizen:/scripting/lua/scheduler.lua:41: in field ‘CreateThreadNow’
citizen:/scripting/lua/scheduler.lua:218: in function citizen:/scripting/lua/scheduler.lua:182