diff --git a/Services/client/src/stores/file-info-data.ts b/Services/client/src/stores/file-info-data.ts
index d13bc2f..76965ab 100644
--- a/Services/client/src/stores/file-info-data.ts
+++ b/Services/client/src/stores/file-info-data.ts
@@ -69,7 +69,7 @@ export const useFileInfoStore = defineStore('info', () => {
 
     if (extension) return extension
     if (fileName && fileName.includes('.')) {
-      return fileName.substring(fileName.lastIndexOf('.'))
+      return fileName.substring(fileName.lastIndexOf('.') + 1)
     }
 
     return 'ไม่ทราบประเภท'