PDF/A Document with Metadata

Question

I am trying to get the metadata to work with my PDF/A compliant document.

For some reason, only the title and subject show up.

I am using Overleaf to compile.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%% DEFINE THE METADATA REQUIRED FOR PDF/A %%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\pdfinfo{
  /Author (Author Name)
  /Title (Title Here)
  /Subject (PhD Thesis)
  /Keywords (Keyword1, Keyword2)
  /Publisher (Publisher here)
}

%%%%%%%%%%%%%%%%%%%%%%%%%
%%% DOCUMENT PREAMBLE %%%
%%%%%%%%%%%%%%%%%%%%%%%%%

\documentclass[letterpaper, hidelinks, oneside, 12pt]{report}
\usepackage[letterpaper, left=1.5in, top=1in, bottom=1in, right=1in, nohead, includefoot]{geometry}
\usepackage[toc, page]{appendix}
\usepackage{setspace}
\usepackage{array}
\usepackage{color}
\usepackage{cancel}
\usepackage{graphicx}
\usepackage{amsmath}
\usepackage{acronym} 
\usepackage{amssymb}
\usepackage{bm}
\usepackage{multirow}
\usepackage{enumitem}
\usepackage{booktabs}
\usepackage[a-3b]{pdfx}
\usepackage{parskip}
\usepackage{calc}

\begin{document}
Words
\end{document}

EDIT

As mentioned regarding pdfx I have also tried the following instead of the pdfinfo technique; however, NO metadata shows up.

\begin{filecontents*}{Thesis.xmpdata}
    \Title{Title Here}
    \Author{Author Name}
    \Subject{Subj Here}
    \Keywords{Keyword1 \sep Keyword2}
\end{filecontents*}

Answer 1

I discurage using /pdfinfo directly. This writes metadata in the documentinfo dictionary which is a deprecated pdf feature today. The better way is to store metadata is as XMP. See generate PDF/A-1b answer how to do this.

With Metadata as XMP you can generate author lists. pdfauthor={author1,author2} generates

      <dc:creator>
        <rdf:Seq>
          <rdf:li>author1</rdf:li>
          <rdf:li>author2</rdf:li>
        </rdf:Seq>
      </dc:creator>

This will result in better accessibility to search engines.

I discourage using package pdfx which could do the same. But pdfx has disadvantages as you have already found out. It may include an outdated .xmpdata file.