Async function in MS RPC

Question

I'm trying to organize data transfer between the server and the client. When using asynchronous calls using the MS RPC API, I was able to transfer data with the int type to the client side. But when I try to pass in a data structure, I'm having trouble.

idl file

interface Test
{
    typedef struct _RPCData {
        int length;
        [size_is(length)] char* buffer;
    } RPCData, * PRPCData;

    RPCData* TransferData([in] handle_t hBinding, [in] RPCData* sendData);
}

Server

/* [async] */ void TransferData(
    /* [in] */ IN OUT PRPC_ASYNC_STATE TransferData_AsyncHandle,
    /* [in] */ handle_t hBinding,
    /* [in] */ RPCData* sendData)
{
    RPCData data;
    data.buffer = (unsigned char*)"Test data";
    data.length = 9;

    RpcAsyncCompleteCall(TransferData_AsyncHandle, &data); // There's error here

      ...
}

Client

void SendData(LPCWSTR lpwszProto, LPCWSTR lpwszEndPoint, LPCWSTR lpwszHost, RPCData data)
{
    ...
    RPC_ASYNC_STATE async;
    RPC_WSTR szStringBinding = nullptr;
    RpcStringBindingCompose(nullptr,lpwszProto,lpwszHost,lpwszEndPoint, nullptr, &szStringBinding);
    RpcBindingFromStringBinding(szStringBinding, &PPE_IfHandle);
    
    async.UserInfo = NULL;
    async.NotificationType = RpcNotificationTypeEvent;
    async.u.hEvent = CreateEvent(NULL, FALSE, FALSE, NULL);

    RpcAsyncInitializeHandle(&async, sizeof(RPC_ASYNC_STATE));

    RPCData reciveData;

    if (async.u.hEvent != 0)
    {
        RpcTryExcept

            TransferData(&async, TEST_IfHandle, &data);

            if (WaitForSingleObject(async.u.hEvent, INFINITE) == WAIT_FAILED) {}

            RPCData reciveData;
            RpcAsyncCompleteCall(&async, &reciveData);
        
        RpcExcept(1)
        
                      ....
        
        RpcEndExcept
    }
        
    CloseHandle(async.u.hEvent);
    ...

}

As a result I get an error on the server:

Exception thrown at 0x763B0879 (rpcrt4.dll) in ServerDebug.exe: 0xC0000005: Access violation reading location 0x0000000D.

All examples of using asynchronous calls use int.