diff --git a/packages/webpack-plugin/lib/react/processStyles.js b/packages/webpack-plugin/lib/react/processStyles.js
index ca6bbeac35..063593c650 100644
--- a/packages/webpack-plugin/lib/react/processStyles.js
+++ b/packages/webpack-plugin/lib/react/processStyles.js
@@ -63,6 +63,7 @@ module.exports = function (styles, {
             };\n
             let __unoClassMap
             global.__getUnoClassMap = function () {
+              const formatValue = global.__formatValue
               if (!__unoClassMap) {
                 __unoClassMap = __unoCssMapPlaceholder__
               }