diff --git a/EnvelopeGenerator.Application/Extensions/DTOExtensions.cs b/EnvelopeGenerator.Application/Extensions/DTOExtensions.cs
index 8c88b34f..f1cd28ca 100644
--- a/EnvelopeGenerator.Application/Extensions/DTOExtensions.cs
+++ b/EnvelopeGenerator.Application/Extensions/DTOExtensions.cs
@@ -1,4 +1,6 @@
 using EnvelopeGenerator.Application.DTOs.Receiver;
+using EnvelopeGenerator.Extensions;
+using Newtonsoft.Json;
 
 namespace EnvelopeGenerator.Application.Extensions
 {
@@ -12,5 +14,9 @@ namespace EnvelopeGenerator.Application.Extensions
 
         public static bool IsTotpSecretValid(this ReceiverReadDto dto, int minutesBeforeExpiration = 30)
             => !dto.IsTotpSecretInvalid(minutesBeforeExpiration);
+
+        public static bool IsTotpValid(this ReceiverReadDto dto, string totp) => dto.TotpSecretkey is null ? throw new ArgumentNullException(nameof(dto), $"TotpSecretkey of DTO cannot validate without TotpSecretkey. Dto: {JsonConvert.SerializeObject(dto)}") : totp.IsValidTotp(dto.TotpSecretkey);
+
+        public static bool IsTotpInvalid(this ReceiverReadDto dto, string totp) => !dto.IsTotpValid(totp: totp);
     }
 }
\ No newline at end of file
diff --git a/EnvelopeGenerator.Web/Controllers/HomeController.cs b/EnvelopeGenerator.Web/Controllers/HomeController.cs
index 1dacd4e0..aa7b8ea8 100644
--- a/EnvelopeGenerator.Web/Controllers/HomeController.cs
+++ b/EnvelopeGenerator.Web/Controllers/HomeController.cs
@@ -258,7 +258,7 @@ namespace EnvelopeGenerator.Web.Controllers
                             }
                             else if (auth.HasAuthenticatorCode)
                             {
-                                if (!auth.AuthenticatorCode!.IsValidTotp(er_secret.Receiver!.TotpSecretkey!))
+                                if (er_secret.Receiver!.IsTotpInvalid(totp: auth.AuthenticatorCode!))
                                 {
                                     Response.StatusCode = StatusCodes.Status401Unauthorized;
                                     ViewData["ErrorMessage"] = _localizer[WebKey.WrongAccessCode].Value;