diff --git a/td/telegram/ClientJson.cpp b/td/telegram/ClientJson.cpp
index f817f70d8..d6c543f56 100644
--- a/td/telegram/ClientJson.cpp
+++ b/td/telegram/ClientJson.cpp
@@ -41,8 +41,7 @@ static std::pair<td_api::object_ptr<td_api::Function>, string> to_request(Slice
 
   string extra;
   if (has_json_object_field(json_value.get_object(), "@extra")) {
-    extra = json_encode<string>(
-        get_json_object_field(json_value.get_object(), "@extra", JsonValue::Type::Null).move_as_ok());
+    extra = json_encode<string>(get_json_object_field_force(json_value.get_object(), "@extra"));
   }
 
   td_api::object_ptr<td_api::Function> func;