BibTeX does not have the right entry for preprints. This is a hack for producing the correct reference:
@booklet{EasyChair:833,
author = {Sultan Almalki and Kaushik Roy and Prosenjit Chatterjee},
title = {Continuous Authentication Using Mouse Clickstream Data Analysis},
howpublished = {EasyChair Preprint 833},
year = {EasyChair, 2019}}