A group field has sub fields. Is about_schema the group field name or is that one of the sub fields?
… looking back at OP, you said
In this var_dump I can’t see the values added from ACF field.
values for ACF fields are not added to the Term object.
$field_value = get_field('about_schema', $term, true);
The value of the field will be in $field_value
