diff --git a/instruct/handlers.py b/instruct/handlers.py
index 9ad63c5..ad091da 100644
--- a/instruct/handlers.py
+++ b/instruct/handlers.py
@@ -27,7 +27,7 @@ def _get_user_cn(user_id: str) -> str:
     user_id из TrueConf — это обычно email, например 'ds.krivochenko@tcs.sibcem.ru'
     Заменяет tcs.sibcem.ru на sibcem.ru для поиска в AD.
     """
-    from ldap3 import Server, Connection, ALL
+    from ldap3 import Server, Connection, ALL, SUBTREE
     from config.config import AD_SERVER, AD_USER, AD_PASSWORD, AD_BASE
     from ldap3.utils.conv import escape_filter_chars
 
@@ -43,25 +43,36 @@ def _get_user_cn(user_id: str) -> str:
         server = Server(AD_SERVER, get_info=ALL)
         conn = Connection(server, user=AD_USER, password=AD_PASSWORD, auto_bind=True)
 
-        # Пробуем несколько фильтров
+        # Пробуем несколько фильтров + разные базы поиска
         filters = [
             f"(mail={safe_id})",
             f"(userPrincipalName={safe_id})",
             f"(sAMAccountName={safe_short})",
         ]
-        for filt in filters:
-            conn.search(AD_BASE, f"(&(objectClass=user)({filt}))", attributes=["cn", "sAMAccountName", "mail"])
-            if conn.entries:
-                entry = conn.entries[0]
-                cn = str(entry.cn)
-                mail = str(entry.mail) if 'mail' in entry else "N/A"
-                sam = str(entry.sAMAccountName) if 'sAMAccountName' in entry else "N/A"
-                logger.info(f"AD found: cn={cn}, mail={mail}, sam={sam}")
-                return cn
+
+        # AD_BASE + корень домена для поиска во всём дереве
+        search_bases = [AD_BASE, "DC=sibcem,DC=ru"]
+
+        for base in search_bases:
+            for filt in filters:
+                conn.search(
+                    search_base=base,
+                    search_filter=f"(&(objectClass=user)({filt}))",
+                    attributes=["cn", "sAMAccountName", "mail", "userPrincipalName"],
+                    search_scope=SUBTREE
+                )
+                if conn.entries:
+                    entry = conn.entries[0]
+                    cn = str(entry.cn)
+                    mail = str(entry.mail) if 'mail' in entry else "N/A"
+                    sam = str(entry.sAMAccountName) if 'sAMAccountName' in entry else "N/A"
+                    upn = str(entry.userPrincipalName) if 'userPrincipalName' in entry else "N/A"
+                    logger.info(f"AD found: cn={cn}, mail={mail}, sam={sam}, upn={upn}, base={base}")
+                    return cn
 
         logger.warning(f"AD not found for user_id={user_id}, search_id={search_id}, short={short_username}")
     except Exception as e:
-        logger.error(f"Ошибка получения CN из AD для {user_id}: {e}")
+        logger.error(f"Ошибка получения CN из AD для {user_id}: {e}", exc_info=True)
     return user_id  # fallback — используем user_id как CN