Biblatex does not reverse the first and last names of the second author

Question

I have the following .bib file:

@Book{sample-book,
    author="First1 Last1 and First2 Last2",
    title="A sample book",
    publisher="Public Domain Books",
}

Then I use lualatex biber lualatex lualatex to generate the pdf file.

However, the generated entry would look like this:

Last1, First1 and First2 Last2, A sample book, Public Domain Books

My biblatex package settings:

\usepackage[
    bibstyle=mla,
    style=authortitle,
    %style=authortitle-tcomp,
    %firstinits=true,
    %backref=true,
    natbib=true,
    backend=biber
]{biblatex}

Answer 1

This seems to be a feature (not a bug) of the mla style that you are using: the first author is written as "Last, First" and all subsequent authors are written as "First Last".

See some examples at the end of http://owl.english.purdue.edu/owl/resource/747/01/

Answer 2

You can just add

\DeclareNameAlias{sortname}{last-first}

after the \usepackage[...]{biblatex}.