Nvidia NVEnc output corrupt when enableSubFrameWrite = 1

Question

My preset:

m_stEncodeConfig.encodeCodecConfig.hevcConfig.sliceMode = 3u;
m_stEncodeConfig.encodeCodecConfig.hevcConfig.sliceModeData = (uint32_t)m_stEncodeStreamInfo.nMaxSliceNum; //4
m_stCreateEncodeParams.reportSliceOffsets = 1;
m_stCreateEncodeParams.enableSubFrameWrite = 1;

code of process output:

NV_ENC_LOCK_BITSTREAM lockBitstreamData;
memset(&lockBitstreamData, 0, sizeof(lockBitstreamData));
lockBitstreamData.version = NV_ENC_LOCK_BITSTREAM_VER;
lockBitstreamData.outputBitstream = pEncodeBuffer->stOutputBfr.hBitstreamBuffer;
lockBitstreamData.doNotWait = 1u;
std::vector<uint32_t> arrSliceOffset(m_stEncodeConfig.encodeCodecConfig.hevcConfig.sliceModeData);
lockBitstreamData.sliceOffsets = arrSliceOffset.data();
while (true)
{
    NVENCSTATUS status = m_pEncodeAPI->nvEncLockBitstream(m_hEncoder, &lockBitstreamData);
    auto tick = int(std::chrono::steady_clock::now().time_since_epoch().count() / 1000000);
    if (status == NVENCSTATUS::NV_ENC_SUCCESS)
    {
        if (lockBitstreamData.hwEncodeStatus == 2)
        {
            static std::ofstream of("slice.h265", std::ios::trunc | std::ios::binary);
            of.write((char*)lockBitstreamData.bitstreamBufferPtr, lockBitstreamData.bitstreamSizeInBytes);
            of.flush();
            break;
        }
        NVENCAPI_CALL_CHECK(m_pEncodeAPI->nvEncUnlockBitstream(m_hEncoder, lockBitstreamData.outputBitstream));
    }
    else
    {
        break;
    }
}

play bitstream:

ffplay -i slice.h265

1. output : Packet corrupt
2. arrSliceOffset[0] always = 255.

I watch the memory from VS Debug and compare with enableSubFrameWrite = 0,the bitstreamSizeInBytes less of valid data size . It’s BUG or I loss some details? Anybady can tell me how can I correct use of enableSubFrameWrite