diff --git a/NFCLockDemoV2/Platforms/Android/NFCLockHelper.cs b/NFCLockDemoV2/Platforms/Android/NFCLockHelper.cs
index e678198..7812c41 100644
--- a/NFCLockDemoV2/Platforms/Android/NFCLockHelper.cs
+++ b/NFCLockDemoV2/Platforms/Android/NFCLockHelper.cs
@@ -2,7 +2,6 @@
 using Android.Content;
 using Android.Nfc;
 using Android.Nfc.Tech;
-using AndroidX.Activity;
 using Com.Lvcheng.Lock.Shared.Nfc.Example.Java;
 using NFCLockAppV2;
 using NFCLockDemoV2.Platforms.Android;
@@ -77,7 +76,7 @@ public class NFCLockHelper
                     }
                     finally
                     {
-                        await Task.Delay(2000);
+                        await Task.Delay(1000);
                         _processing = false;
                         _callbacks.OnFinished();
                     }
@@ -106,9 +105,9 @@ public class NFCLockHelper
                         return;
 
                     _ = wrapper.Rssi;
-                    id = wrapper.MGetId().LongValue();
-                    isNew = wrapper.MGetIsNew().BooleanValue();
-                    mRssi = wrapper.MGetRssi().IntValue();
+                    id = wrapper.MGetId()?.LongValue() ?? null;
+                    isNew = wrapper.MGetIsNew()?.BooleanValue() ?? null;
+                    mRssi = wrapper.MGetRssi()?.IntValue() ?? null;
 
                     bool continueLoop = _callbacks.OnLoop(wrapper, id, isNew, mRssi);