How to connect multiple slave devices under the modbus-serial (rtu) connector

Question

this is my Configuration File. I'm using the new profile https://thingsboard.io/docs/iot-gateway/config/modbus/ [new_modbus.json], in the new configuration file, seems to be able to configure several different devices in { master : { "slaves" : [] }}. And when I do, I couldn't get the right results.

{
    "master":{
        "slaves":[
            {
                "unitId":1,
                "deviceName":"test1",
                "attributesPollPeriod":5000,
                "timeseriesPollPeriod":5000,
                "sendDataOnlyOnChange":false,
                "attributes":[
                    {
                        "byteOrder":"BIG",
                        "tag":"temperature",
                        "type":"bytes",
                        "functionCode":3,
                        "registerCount":1,
                        "address":1
                    }
                ],
                "timeseries":[
                    {
                        "tag":"distance",
                        "type":"bytes",
                        "functionCode":3,
                        "objectsCount":1,
                        "address":2
                    }
                ],
                "attributeUpdates":[
                    {
                        "tag":"shared_value_1",
                        "type":"32uint",
                        "functionCode":6,
                        "objectsCount":2,
                        "address":3
                    },
                    {
                        "tag":"shared_value_2",
                        "type":"32uint",
                        "functionCode":6,
                        "objectsCount":2,
                        "address":4
                    }
                ],
                "rpc":[
                    {
                        "tag":"bearing_bpfo",
                        "type":"32uint",
                        "functionCode":6,
                        "objectsCount":2,
                        "address":5
                    }
                ],
                "host":null,
                "port":"/dev/ttyUSB0",
                "type":"serial",
                "method":"rtu",
                "timeout":35,
                "byteOrder":"BIG",
                "wordOrder":"BIG",
                "retries":null,
                "retryOnEmpty":null,
                "retryOnInvalid":null,
                "baudrate":9600,
                "pollPeriod":5000,
                "connectAttemptCount":1
            },
            {
                "unitId":2,
                "deviceName":"Test2",
                "attributesPollPeriod":5000,
                "timeseriesPollPeriod":5000,
                "sendDataOnlyOnChange":false,
                "attributes":[
                    {
                        "byteOrder":"BIG",
                        "tag":"temperature",
                        "type":"bytes",
                        "functionCode":3,
                        "registerCount":1,
                        "address":10
                    }
                ],
                "timeseries":[
                    {
                        "tag":"distance",
                        "type":"bytes",
                        "functionCode":3,
                        "objectsCount":1,
                        "address":11
                    }
                ],
                "attributeUpdates":[
                    {
                        "tag":"shared_value_1",
                        "type":"32uint",
                        "functionCode":6,
                        "objectsCount":2,
                        "address":12
                    }
                ],
                "host":null,
                "port":"/dev/ttyUSB0",
                "type":"serial",
                "method":"rtu",
                "timeout":35,
                "byteOrder":"BIG",
                "wordOrder":"BIG",
                "retries":null,
                "retryOnEmpty":null,
                "retryOnInvalid":null,
                "baudrate":9600,
                "pollPeriod":5000,
                "connectAttemptCount":5
            }
        ]
    },
    "slave":null
}

The Connector name I am using is the Modbus Connector, and the version information for my deployment is as follows：
OS: Raspberry Pi
Thingsboard IoT Gateway version : 3.0.1
Python version : 3.9.2

Error traceback:

    ""2022-05-11 15:28:10" - |DEBUG| - [bytes_modbus_uplink_converter.py] - bytes_modbus_uplink_converter - convert - 87 - datatype: telemetry   key: distance   value: None"
    ""2022-05-11 15:28:10" - |DEBUG| - [bytes_modbus_uplink_converter.py] - bytes_modbus_uplink_converter - convert - 92 - {'deviceName': 'testUpdate', 'deviceType': 'default', 'telemetry': [], 'attributes': []}"
    ""2022-05-11 15:28:10" - |ERROR| - [bytes_modbus_uplink_converter.py] - bytes_modbus_uplink_converter - convert - 83 - Modbus Error: [Input/Output] device reports readiness to read but returned no data (device disconnected or multiple access on port?)"
    NoneType: None
    ""2022-05-11 15:28:10" - |DEBUG| - [bytes_modbus_uplink_converter.py] - bytes_modbus_uplink_converter - convert - 87 - datatype: telemetry   key: distance   value: None"
    ""2022-05-11 15:28:10" - |DEBUG| - [bytes_modbus_uplink_converter.py] - bytes_modbus_uplink_converter - convert - 92 - {'deviceName': 'RpcTest', 'deviceType': 'default', 'telemetry': [], 'attributes': []}"
    ""2022-05-11 15:28:10" - |ERROR| - [bytes_modbus_uplink_converter.py] - bytes_modbus_uplink_converter - convert - 83 - Modbus Error: [Input/Output] device reports readiness to read but returned no data (device disconnected or multiple access on port?)"
    NoneType: None