diff --git a/src/mixins/itext_behavior.mixin.js b/src/mixins/itext_behavior.mixin.js
index bbbeec85..5182fb01 100644
--- a/src/mixins/itext_behavior.mixin.js
+++ b/src/mixins/itext_behavior.mixin.js
@@ -647,13 +647,13 @@
       if (lineStart !== lineEnd) {
         // step1 remove the trailing of lineStart
         if (this.styles[lineStart]) {
-          for (i = charStart; i < this._textLines[lineStart].length; i++) {
+          for (i = charStart; i < this._unwrappedTextLines[lineStart].length; i++) {
             delete this.styles[lineStart][i];
           }
         }
         // step2 move the trailing of lineEnd to lineStart if needed
         if (this.styles[lineEnd]) {
-          for (i = charEnd; i < this._textLines[lineEnd].length; i++) {
+          for (i = charEnd; i < this._unwrappedTextLines[lineEnd].length; i++) {
             styleObj = this.styles[lineEnd][i];
             if (styleObj) {
               this.styles[lineStart] || (this.styles[lineStart] = { });