local error

1x AIBot\Core.lua:616: bad argument #1 to "sub" (string expected, got nil)
<in C code>
AIBot\Core.lua:616: in function "?"
Libs\CallbackHandler-1.0\CallbackHandler-1.0-6.lua:147: in function <Libs\CallbackHandler-1.0\CallbackHandler-1.0.lua:147>
<string>:"safecall Dispatcher[16]":4: in function <string>:"safecall Dispatcher[16]":4
<in C code>
<string>:"safecall Dispatcher[16]":13: in function "?"
Libs\CallbackHandler-1.0\CallbackHandler-1.0-6.lua:92: in function "Fire"
AIBot\Libs\AceEvent-3.0\AceEvent-3.0-3.lua:120: in function <AIBot\Libs\AceEvent-3.0\AceEvent-3.0.lua:119>

Locals:
nil