I would like to create a surface plot (like the one shown below) from a .csv table containing three columns of data (x,y,phi) but all I get is a line plot (see second picture). The data table is downloadable from the provided link. If anyone knows how to get around this issue your help would be much appreciated.
\documentclass[12pt,a4paper]{report}
\usepackage[utf8]{inputenc}
\usepackage{filecontents}
\usepackage{pgfplots}
\pgfplotsset{compat=1.17}
\begin{document}
\section{Contour Plot}
\begin{tikzpicture} \begin{axis}[
title={computational potential}, xmin=-3, xmax=3, ymin=0, ymax=3,
view={0}{90},
colorbar horizontal,
mesh/ordering=x varies,
]
\addplot3 [surf,
] table [col sep=comma] {computational_potential.csv}; \end{axis}
\end{tikzpicture}
\end{document}

