It happened again and I captured it!
Error
rpg/adventure.lua:352: attempt to call field 'setAreaFlag' (a nil value)
Traceback
[love "callbacks.lua"]:228: in function 'handler'
rpg/adventure.lua:352: in function 'onTypeDeath'
rpgenemy.lua:162: in function 'onDeath'
rpgview.lua:1150: in function 'onEnd'
rpgview.lua:1374: in function 'update'
main.lua:113: in function 'update'
[love "callbacks.lua"]:162: in function <[love "callbacks.lua"]:144>
[C]: in function 'xpcall'