# Error when using the els-cas template in Texmaker

I'm quite new to the els-cas-dc template in LaTeX. I want to submit a paper to Elsevier, thus I downloaded the "els-cas-templates" package. Specifically, my paper is a two column paper so I'm trying to use the els-cas-dc class. When I compile in TeXmaker on my MacBook, I get the following error message:

"/usr/local/texlive/2022/texmf-dist/tex/latex/els-cas-templates/cas- dc.cls Error line 61 !LaTeX Error: File expl3.sty' not found.Type X to quit or to proceed,or enter new name. (Default extension: sty)Enter file name:! Emergency stop. @ifundefined"

The following is the code I'm have written:

\documentclass[a4paper,fleqn]{cas-dc}
\usepackage{booktabs,siunitx}
\usepackage{natbib}
\usepackage{geometry}
\sisetup{detect-all}
%\usepackage{cite}
\usepackage{amssymb,amsthm}
\emergencystretch=27pt %Allow 27pt of additional white space per line in order to avoid underfull/overfull lines
\hyphenpenalty=10000 %Prevent hyphenation if word is too long for line
\ExplSyntaxOn
\keys_set:nn { stm / mktitle } { nologo }
\ExplSyntaxOff
\begin{document}
\shorttitle{Adoption of Cocoa Agroforestry Technology and Productivity}
\shortauthors{Felix Larry Essilfie}
%\begin{frontmatter}

\title [mode = title]{Adoption of Cocoa Agroforestry Technology and Productivity: An Application of the Regression Adjustment Method with Weighting }
\author[1,2]{Felix Larry Essilfie}%[orcid=0000-0002-9398-9414]
%\author[3]{Noor Islam}
%\author[1]{Khurram Saleem Alimgeer}
%\author[1]{Ammar Ali}

\cortext[cor1]{Corresponding author}
\cormark[1]
\address[1]{Institute of Development and Economic Research, No. 24 Bugatti St., Asheyie-Down, Adenta, Accra, Ghana}
%\address[3]{CECOS University of IT \& Emerging Sciences, Peshawar 25124, Pakistan}
%\address[4]{Wah Engineering College, University of Wah, Wah Cantt 47070, Pakistan}
%and Khurram Saleem Alimgeer$^1$

\begin{abstract}[S U M M A R Y]
The study uses a sample of 1,175 cocoa farmers to assess the effects of cocoa agroforestry technology on the productivity of maize farmers. An approach that combines the regression adjustment method with weighting to estimate the treatment parameters was employed for the study. The approach is a generalization of the doubly robust estimation methods for different treatment parameters, which are defined in a multivalued treatment effect estimation framework.\par
\end{abstract}

\begin{keywords}
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