diff --git a/packages/macros.sty b/packages/macros.sty
index cf3193c..2aa364f 100644
--- a/packages/macros.sty
+++ b/packages/macros.sty
@@ -54,7 +54,7 @@
 \newenvironment{corollary_sq}{\begin{mdframed}\begin{corollary}}{\end{corollary}\end{mdframed}}
 \DeclarePairedDelimiter{\generator}{\langle}{\rangle}
 \DeclareMathOperator{\subgroup}{\leqslant}
-\DeclareMathOperator{\normalSubgroup}{\triangleleft}
+\DeclareMathOperator{\normalSubgroup}{\trianglelefteq}
 \newcommand{\rank}[1]{\text{rg}(#1)}
 \DeclarePairedDelimiter{\norm}{\lVert}{\rVert}
 \DeclarePairedDelimiter{\Norm}{\lVert}{\rVert}