diff --git a/Packages/com.teach310.core-bluetooth-for-unity/Runtime/NativeMethods.cs b/Packages/com.teach310.core-bluetooth-for-unity/Runtime/NativeMethods.cs
index 89477d5..ad824ad 100644
--- a/Packages/com.teach310.core-bluetooth-for-unity/Runtime/NativeMethods.cs
+++ b/Packages/com.teach310.core-bluetooth-for-unity/Runtime/NativeMethods.cs
@@ -25,9 +25,6 @@ int identifierSize
         [DllImport(DLL_NAME, CallingConvention = CallingConvention.Cdecl)]
         internal static extern SafeNativeCentralManagerHandle cb4u_central_manager_new(IntPtr options);
 
-        [DllImport(DLL_NAME, CallingConvention = CallingConvention.Cdecl)]
-        internal static extern void cb4u_central_manager_release(IntPtr handle);
-
         internal delegate void CB4UCentralManagerDidConnectHandler(IntPtr centralPtr, IntPtr peripheralIdPtr);
         internal delegate void CB4UCentralManagerDidDisconnectPeripheralHandler(IntPtr centralPtr, IntPtr peripheralIdPtr, int errorCode);
         internal delegate void CB4UCentralManagerDidFailToConnectHandler(IntPtr centralPtr, IntPtr peripheralIdPtr, int errorCode);