diff --git a/AsbCloudApp/Data/UserDto.cs b/AsbCloudApp/Data/UserDto.cs
index 15cc5408..ed065f60 100644
--- a/AsbCloudApp/Data/UserDto.cs
+++ b/AsbCloudApp/Data/UserDto.cs
@@ -58,5 +58,25 @@
         /// DTO компании
         /// </summary>
         public CompanyDto Company { get; set; }
+
+        /// <summary>
+        /// Получение отображаемого имени
+        /// </summary>
+        /// <returns></returns>
+        public string MakeDisplayName()
+        {
+            if (string.IsNullOrEmpty(Surname))
+                return Login;
+
+            var s = Surname;
+            if (!string.IsNullOrEmpty(Name))
+            {
+                s += $"{Name[0]}.";
+                if (!string.IsNullOrEmpty(Patronymic))
+                    s += $" {Patronymic[0]}.";
+            }
+
+            return s;
+        }
     }
 }
diff --git a/AsbCloudInfrastructure/Repository/UserRepository.cs b/AsbCloudInfrastructure/Repository/UserRepository.cs
index 9ea6979e..1502375a 100644
--- a/AsbCloudInfrastructure/Repository/UserRepository.cs
+++ b/AsbCloudInfrastructure/Repository/UserRepository.cs
@@ -183,9 +183,9 @@ namespace AsbCloudInfrastructure.Repository
         {
             var existingUserDto = (await GetCacheUserAsync(token))
                 .FirstOrDefault(u => u.Login.ToLower() == login.ToLower());
-            var existingUser = Convert(existingUserDto);
-            if (existingUser is not null)
-                throw new ArgumentInvalidException($"Login {login} is busy by {existingUser.MakeDisplayName()}, id{existingUser.Id}", nameof(login));
+
+            if (existingUserDto is not null)
+                throw new ArgumentInvalidException($"Login {login} is busy by {existingUserDto.MakeDisplayName()}, id{existingUserDto.Id}", nameof(login));
         }
 
         private Task<IEnumerable<UserExtendedDto>> GetCacheUserAsync(CancellationToken token)