BibTeX does not have the right entry for preprints. This is a hack for producing the correct reference:
@Booklet{EasyChair:10539,
author = {R Thanuj Kumar and R Senthilkumar},
title = {E-Learning in Vernacular Language},
howpublished = {EasyChair Preprint no. 10539},
year = {EasyChair, 2023}}