Biblatex not finding citations

Question

I have been going out of my mind trying to fix this problem. I recently moved from natbib to biblatex, as a lot of my references contain unicode characters. My citations used to work find using natbib, but since I have moved across to biblatex, they are not being found, resulting in the following:

Below is my minimal working example:

\documentclass[twoside,a4paper, 12pt]{memoir}


%Citations
\usepackage{babel}
\usepackage{csquotes}
\usepackage[citestyle=alphabetic,bibstyle=authoryear]{biblatex}
\addbibresource{test.bib}

\begin{document}

Sed ut perspiciatis \parencite{wilk1968}.

\printbibliography


\end{document}

My .bib file (test.bib), which is located in the same directory as the .tex file is shown below:

@article{wilk1968,
  langid = {english},
  title = {Probability {{Plotting Methods}} for the {{Analysis}} of {{Data}}},
  volume = {55},
  issn = {00063444},
  url = {https://www.jstor.org/stable/2334448?origin=crossref},
  doi = {10.2307/2334448},
  abstract = {This paper describes and discusses graphical techniques, based on the primitive empirical cumulative distribution function and on quantile (Q-Q) plots, percent (P-P) plots and hybrids of these, which are useful in assessing a one-dimensional sample, either from original data or resulting from analysis. Areas of application include: the comparison of samples; the comparison of distributions; the presentation of results on sensitivities of statistical methods; the analysis of collections of contrasts and of collections of sample variances; the assessment of multivariate contrasts;\_ and the structuring of analysis of variance mean squares. Many of the objectives and techniques are illustrated by examples.},
  number = {1},
  journaltitle = {Biometrika},
  urldate = {2018-06-01},
  date = {1968-03},
  pages = {1},
  author = {Wilk, M. B. and Gnanadesikan, R.},
  file = {}
}

My .bib file was exported using Better BibLaTeX from Zotero. Any help is greatfully received.