The super table parameter continueIfFail: 0, STOP insertion!

I am trying to use taosbenchmark to test the performance. I have created a super table with 500 columns and the last one is c499. Now, I want to insert a new column called c500 into all of the sub-tables using this json file.

{
    "filetype": "insert",
    "cfgdir": "/etc/taos",
    "host": "127.0.0.1",
    "port": 6030,
    "user": "root",
    "connection_pool_size": 8,
    "thread_count": 16,
    "result_file": "insert_res.txt",
    "confirm_parameter_prompt": "no",
    "insert_interval": 0,
    "interlace_rows": 0,
    "num_of_records_per_req": 10000,
    "prepared_rand": 10000,
    "chinese": "no",
    "databases": [
        {
            "dbinfo": {
                "name": "test",
                "drop": "no",
                "replica": 1,
                "precision": "ms"
            },
            "super_tables": [
                {
                    "name": "meters",
                    "child_table_exists": "yes",
                    "childtable_count": 1000,
                    "childtable_prefix": "d",
                    "escape_character": "yes",
                    "auto_create_table": "no",
                    "batch_create_tbl_num": 5,
                    "data_source": "rand",
                    "insert_mode": "taosc",
                    "non_stop_mode": "no",
                    "insert_rows": 10000,
                    "childtable_limit": 1000,
                    "childtable_offset": 0,
                    "interlace_rows": 0,
                    "partial_col_num": 0,
                    "disorder_ratio": 50,
                    "columns": [
                        {
                            "type": "FLOAT",
                            "name": "c500",
                            "count": 1,
                            "max": 30,
                            "min": 1
                        }
                    ]
                }
            ]
        }
    ]
}

However, when I use this json file to do insertion, I met this error: WARN: The super table parameter continueIfFail: 0, STOP insertion!. Where am I wrong?