Why auto name won’t work?
It get employee_name instead of naming_series.
Check in Setup > Naming Series for Attendance DocType what is the naming series set.
This is the naming series. But still it get what is on the title_field.
When you make a new attendance, check what is the series, it will take that is mentioned there, screenshot attached:
If this does not happen, then go to Customize Form and check the series that is mentioned there, screenshot attached:
Hope this helps.