Control sorting in Library display:
But ..
IIRC There is also one more setting
author_sort_copy_method , yours is set to invert
Displays Fn Ln Sorts Ln, Fn
I think you want 'Copy'
Displays Fn Ln Sorts Fn Ln
Note: you will need to force a re-calculate of the sort value;
One way: Select All; tap the 'E' key: tick the automatic set Author sort box: Apply