diff --git a/app/Services/TG/Hook/Dog.php b/app/Services/TG/Hook/Dog.php
index 22eab46..6c5bcbf 100644
--- a/app/Services/TG/Hook/Dog.php
+++ b/app/Services/TG/Hook/Dog.php
@@ -270,6 +270,11 @@ class Dog extends Mod\Base {
     }
     
     private function subStr($input) {
+        
+        if (!$input) {
+            return $input;
+        }
+        
         if (mb_strlen($input, 'UTF-8') > (int) $this->iStrMaxLen) {
             
             return mb_substr($input, 0, (int) $this->iStrMaxLen, 'UTF-8')."……";