diff --git a/pynitrokey/nk3/piv_app.py b/pynitrokey/nk3/piv_app.py
index 33378fe9..90e685fe 100644
--- a/pynitrokey/nk3/piv_app.py
+++ b/pynitrokey/nk3/piv_app.py
@@ -3,6 +3,7 @@
 from typing import Any, Callable, Optional, Sequence, Union
 
 import smartcard
+from cryptography.hazmat.decrepit.ciphers.algorithms import TripleDES
 from cryptography.hazmat.primitives import hashes
 from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
 from smartcard.CardConnection import CardConnection
@@ -168,8 +169,8 @@ def authenticate_admin(self, admin_key: bytes) -> None:
 
         if len(admin_key) == 24:
             algorithm: Union[
-                algorithms.TripleDES, algorithms.AES128, algorithms.AES256
-            ] = algorithms.TripleDES(admin_key)
+                TripleDES, algorithms.AES128, algorithms.AES256
+            ] = TripleDES(admin_key)
             # algo = "tdes"
             algo_byte = 0x03
             expected_len = 8