I can't fix this bug
Error while running event enemyracemanager::on_nth_tick(61)
enemyracemanager/lib/quality_processor.lua:279: attempt to index field '?' (a nil value)
stack traceback:
enemyracemanager/lib/quality_processor.lua:279: in function 'get_tier'
enemyracemanager/lib/attack_group_processor.lua:457: in function 'exec'
enemyracemanager/lib/attack_meter_processor.lua:163: in function 'form_group'
enemyracemanager/controllers/cron.lua:51: in function '?'
enemyracemanager/lib/cron_processor.lua:22: in function 'process_one_job'
enemyracemanager/lib/cron_processor.lua:151: in function 'handler'
core/lualib/event_handler.lua:81: in function <core/lualib/event_handler.lua:79>
