diff --git a/app/ldap_protocol/ldap_requests/modify.py b/app/ldap_protocol/ldap_requests/modify.py
index 7ab3333fb..bc55d6403 100644
--- a/app/ldap_protocol/ldap_requests/modify.py
+++ b/app/ldap_protocol/ldap_requests/modify.py
@@ -8,6 +8,7 @@
 from typing import AsyncGenerator, ClassVar
 
 from loguru import logger
+from pydantic import Field
 from sqlalchemy import Select, and_, delete, func, or_, select, update
 from sqlalchemy.exc import IntegrityError
 from sqlalchemy.ext.asyncio import AsyncSession
@@ -110,7 +111,7 @@ class ModifyRequest(BaseRequest):
     # NOTE: If the old value was changed (for example, in _delete)
     # in one method, then you need to have access to the old value
     # from other methods (for example, from _add)
-    _old_vals: dict[str, str | None] = {}
+    old_vals: dict[str, str | None] = Field(default_factory=dict)
 
     @classmethod
     def from_data(cls, data: list[ASN1Row]) -> "ModifyRequest":
@@ -143,7 +144,7 @@ async def _update_password_expiration(
             return
 
         if not (
-            change.modification.type == "krbpasswordexpiration"
+            change.l_type == "krbpasswordexpiration"
             and change.modification.vals[0] == "19700101000000Z"
         ):
             return
@@ -284,10 +285,10 @@ async def handle(
 
                 except MODIFY_EXCEPTION_STACK as err:
                     await ctx.session.rollback()
-                    result_code, message = self._match_bad_response(err)
+                    result_code, error_message = self._match_bad_response(err)
                     yield ModifyResponse(
                         result_code=result_code,
-                        message=message,
+                        error_message=error_message,
                     )
                     return
 
@@ -333,6 +334,9 @@ def _match_bad_response(self, err: BaseException) -> tuple[LDAPCodes, str]:
             case ModifyForbiddenError():
                 return LDAPCodes.OPERATIONS_ERROR, str(err)
 
+            case KRBAPIRenamePrincipalError():
+                return LDAPCodes.UNAVAILABLE, "Kerberos error"
+
             case KRBAPIPrincipalNotFoundError():
                 return LDAPCodes.UNAVAILABLE, "Kerberos error"
 
@@ -632,8 +636,8 @@ def _need_to_cache_samaccountname_old_value(
         return bool(
             directory.entity_type
             and directory.entity_type.name == EntityTypeNames.COMPUTER
-            and change.modification.type == "sAMAccountName"
-            and not self._old_vals.get(change.modification.type),
+            and change.l_type == "samaccountname"
+            and not self.old_vals.get(change.modification.type),
         )
 
     async def _delete(
@@ -689,7 +693,7 @@ async def _delete(
         if self._need_to_cache_samaccountname_old_value(change, directory):
             vals = directory.attributes_dict.get(change.modification.type)
             if vals:
-                self._old_vals[change.modification.type] = vals[0]
+                self.old_vals[change.modification.type] = vals[0]
 
         if attrs:
             del_query = (
@@ -826,14 +830,13 @@ async def _add(  # noqa: C901
         password_use_cases: PasswordPolicyUseCases,
         password_utils: PasswordUtils,
     ) -> None:
+        base_dir = None
         attrs = []
 
         if change.l_type in ("memberof", "member", "primarygroupid"):
             await self._add_group_attrs(change, directory, session)
             return
 
-        base_dir = await self._get_base_dir(directory, session)
-
         for value in change.modification.vals:
             if change.l_type == "useraccountcontrol":
                 uac_val = int(value)
@@ -923,6 +926,12 @@ async def _add(  # noqa: C901
                         new_user_principal_name = str(new_value)
                         new_sam_account_name = new_user_principal_name.split("@")[0]  # noqa: E501  # fmt: skip
                     elif change.l_type == "samaccountname":
+                        if not base_dir:
+                            base_dir = await self._get_base_dir(
+                                directory,
+                                session,
+                            )
+
                         new_sam_account_name = str(new_value)
                         new_user_principal_name = f"{new_sam_account_name}@{base_dir.name}"  # noqa: E501  # fmt: skip
 
@@ -946,12 +955,19 @@ async def _add(  # noqa: C901
                 and directory.entity_type
                 and directory.entity_type.name == EntityTypeNames.COMPUTER
             ):
+                if not base_dir:
+                    base_dir = await self._get_base_dir(
+                        directory,
+                        session,
+                    )
+
                 await self._modify_computer_samaccountname(
                     change,
                     kadmin,
                     base_dir,
                     value,
                 )
+
                 attrs.append(
                     Attribute(
                         name=change.modification.type,
@@ -1019,7 +1035,7 @@ async def _modify_computer_samaccountname(
         base_dir: Directory,
         new_sam_account_name: bytes | str,
     ) -> None:
-        old_sam_account_name = self._old_vals.get(change.modification.type)
+        old_sam_account_name = self.old_vals.get(change.modification.type)
         new_sam_account_name = str(new_sam_account_name)
 
         if not old_sam_account_name: