First uplink fine, second fails with "Drop uplink message - Device not found"

TTN Network and Services The Things Stack v3
4

Thank you for the input. I did follow the link you shared and now it is working as intended with unconfirmed uplinks :slight_smile:
And then I am using this logic as well for restoring from RTC:

However, with confirmed uplinks is another story. It seems like a problem from the lmic library itself.
When a packet is sent and the downlink ack is not received, more packets are sent over and over again, and these subsequent packets are getting drop. I am using the function LMIC_setTxData2 to send the packet.
First confirmed message:

{
  "@type": "type.googleapis.com/ttn.lorawan.v3.UplinkMessage",
  "raw_payload": "gEHg6AEAAwAKjpcC5tjHw31PqNSRwsQWEnTGIVGo3w==",
  "payload": {
    "m_hdr": {
      "m_type": "CONFIRMED_UP"
    },
    "mic": "IVGo3w==",
    "mac_payload": {
      "f_hdr": {
        "dev_addr": "01E8E041",
        "f_ctrl": {},
        "f_cnt": 3
      },
      "f_port": 10,
      "frm_payload": "jpcC5tjHw31PqNSRwsQWEnTG"
    }
  },
  "settings": {
    "data_rate": {
      "lora": {
        "bandwidth": 125000,
        "spreading_factor": 7
      }
    },
    "coding_rate": "4/5",
    "frequency": "867100000",
    "timestamp": 4070255403,
    "time": "2020-07-31T13:54:45.274122Z"
  },
  "rx_metadata": [
    {
      "gateway_ids": {
        "gateway_id": "ic880a",
        "eui": "B827EBFFFE09CD2D"
      },
      "time": "2020-07-31T13:54:45.274122Z",
      "timestamp": 4070255403,
      "rssi": -58,
      "channel_rssi": -58,
      "snr": 9.2,
      "uplink_token": "ChQKEgoGaWM4ODBhEgi4J+v//gnNLRCr1uyUDw==",
      "channel_index": 3
    }
  ],
  "received_at": "2020-07-31T13:54:45.294234522Z",
  "correlation_ids": [
    "gs:conn:01EEDJAZSV3E333PM7ZX209EGZ",
    "gs:uplink:01EEJJENDEKDGYJ36JVCHN706V"
  ]
}

The ack was sent by the gateway but the node did not receive it.
The second message is then sent after 8 seconds:

{
  "@type": "type.googleapis.com/ttn.lorawan.v3.UplinkMessage",
  "raw_payload": "gEHg6AEAAwAKjpcC5tjHw31PqNSRwsQWEnTGIVGo3w==",
  "payload": {
"m_hdr": {
  "m_type": "CONFIRMED_UP"
},
"mic": "IVGo3w==",
"mac_payload": {
  "f_hdr": {
    "dev_addr": "01E8E041",
    "f_ctrl": {},
    "f_cnt": 3
  },
  "f_port": 10,
  "frm_payload": "jpcC5tjHw31PqNSRwsQWEnTG"
}
  },
  "settings": {
"data_rate": {
  "lora": {
    "bandwidth": 125000,
    "spreading_factor": 7
  }
},
"coding_rate": "4/5",
"frequency": "867300000",
"timestamp": 4078402107,
"time": "2020-07-31T13:54:53.422871Z"
  },
  "rx_metadata": [
{
  "gateway_ids": {
    "gateway_id": "ic880a",
    "eui": "B827EBFFFE09CD2D"
  },
  "time": "2020-07-31T13:54:53.422871Z",
  "timestamp": 4078402107,
  "rssi": -54,
  "channel_rssi": -54,
  "snr": 9.5,
  "uplink_token": "ChQKEgoGaWM4ODBhEgi4J+v//gnNLRC79N2YDw==",
  "channel_index": 4
}
  ],
  "received_at": "2020-07-31T13:54:53.446731572Z",
  "correlation_ids": [
"gs:conn:01EEDJAZSV3E333PM7ZX209EGZ",
"gs:uplink:01EEJJEXC70575KTASA1QQ3Q85"
  ]
}

And then the drop occurs:

{
  "@type": "type.googleapis.com/ttn.lorawan.v3.ErrorDetails",
  "namespace": "pkg/gatewayserver",
  "name": "host_handle",
  "message_format": "host `{host}` failed to handle message",
  "attributes": {
    "host": "cluster"
  },
  "cause": {
    "namespace": "pkg/networkserver",
    "name": "device_not_found",
    "message_format": "device not found",
    "correlation_id": "29ffa4cc9bdc446aba7323cb8c231693",
    "code": 5
  },
  "code": 5
}

The raw payload is the same, same frame counter… So it gives the same error.
After 8 tries, fires up an event that TX is complete, without receiving any ack. After that event I have my deep sleep function.

Since the library is re-sending these packets, after the function LMIC_setTxData2, shouldn’t it modify these parameters for each subsequent message?
I guess in these case I need to find a way to stop these subsequent messages or to modify the parameters myself. Any experience with this issue?

PS: According to the guidelines, should I make my posts a bit shorter? :sweat_smile:

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