diff --git a/backend/src/main/java/com/srsystem/util/PhoneEncryptionConverter.java b/backend/src/main/java/com/srsystem/util/PhoneEncryptionConverter.java
index 92d1d78..a8fb59f 100644
--- a/backend/src/main/java/com/srsystem/util/PhoneEncryptionConverter.java
+++ b/backend/src/main/java/com/srsystem/util/PhoneEncryptionConverter.java
@@ -30,6 +30,14 @@ public class PhoneEncryptionConverter implements AttributeConverter<String, Stri
             byte[] padded = new byte[16];
             System.arraycopy(keyBytes, 0, padded, 0, Math.min(keyBytes.length, 16));
             keyBytes = padded;
+        } else if (keyBytes.length < 24) {
+            byte[] padded = new byte[24];
+            System.arraycopy(keyBytes, 0, padded, 0, Math.min(keyBytes.length, 24));
+            keyBytes = padded;
+        } else if (keyBytes.length < 32) {
+            byte[] padded = new byte[32];
+            System.arraycopy(keyBytes, 0, padded, 0, Math.min(keyBytes.length, 32));
+            keyBytes = padded;
         }
         secretKey = new SecretKeySpec(keyBytes, AES);
     }
diff --git a/backend/src/main/resources/application.yml b/backend/src/main/resources/application.yml
index 4ee7412..08bb23a 100644
--- a/backend/src/main/resources/application.yml
+++ b/backend/src/main/resources/application.yml
@@ -43,7 +43,7 @@ parking:
 
 app:
   encryption:
-    phone-key: ${PHONE_ENCRYPTION_KEY:change-me-to-32-chars!!}
+    phone-key: ${PHONE_ENCRYPTION_KEY:0123456789abcdef0123456789abcdef}
 
 file:
   upload-dir: ./uploads