diff --git a/native/jni/src/digraph_utils.cpp b/native/jni/src/digraph_utils.cpp
index 6a1ab02..0834426 100644
--- a/native/jni/src/digraph_utils.cpp
+++ b/native/jni/src/digraph_utils.cpp
@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 
+#include "char_utils.h"
 #include "binary_format.h"
 #include "defines.h"
 #include "digraph_utils.h"
@@ -120,10 +121,11 @@
 /* static */ const DigraphUtils::digraph_t *DigraphUtils::getDigraphForDigraphTypeAndCodePoint(
         const DigraphUtils::DigraphType digraphType, const int compositeGlyphCodePoint) {
     const DigraphUtils::digraph_t *digraphs = 0;
+    const int compositeGlyphLowerCodePoint = toLowerCase(compositeGlyphCodePoint);
     const int digraphsSize =
             DigraphUtils::getAllDigraphsForDictionaryAndReturnSize(digraphType, &digraphs);
     for (int i = 0; i < digraphsSize; i++) {
-        if (digraphs[i].compositeGlyph == compositeGlyphCodePoint) {
+        if (digraphs[i].compositeGlyph == compositeGlyphLowerCodePoint) {
             return &digraphs[i];
         }
     }