Truffle配置Sepolia测试网时出现network_id未指定错误的求助

大家好，我在配置Truffle连接Sepolia测试网时遇到了奇怪的问题——明明已经在配置文件里写了network_id，但运行时还是报错说必须指定这个参数，实在搞不懂哪里出问题了，想请大家帮忙看看。

先附上我的truffle-config.js完整代码：

require("babel-register");
const HDWalletProvider = require("truffle-hdwallet-provider");
require("dotenv").config();
module.exports = {
    networks: {
        Sepolia: {
            provider: function() {
                return new HDWalletProvider(
                    process.env.MNEMONIC,
                    process.env.PROJECT_ENDPOINT,
                    address_index=0,
                    num_addresses=2
                );
            },
            network_id: 11155111    ,
             gas: 4500000,
             gasPrice: 10000000000,
        },
        development: {
            host: process.env.LOCAL_ENDPOINT.split(":")[1].slice(2),
            port: process.env.LOCAL_ENDPOINT.split(":")[2],
            network_id: "*",
        },
        compilers: {
            solc: {
                version: "^0.4.24",
            },
        },
    },
};

我收到的错误提示截图如下：

对应的完整错误日志：

Error: You must specify a network_id in your 'Sepolia' configuration in order to use this network.
at Object.validateNetworkConfig (C:\Users\aditi\AppData\Roaming\npm\node_modules\truffle\build\webpack:\packages\environment\environment.js:136:1)
at Object.detect (C:\Users\aditi\AppData\Roaming\npm\node_modules\truffle\build\webpack:\packages\environment\environment.js:16:1)
at Object.module.exports [as run] (C:\Users\aditi\AppData\Roaming\npm\node_modules\truffle\build\webpack:\packages\core\lib\commands\migrate\run.js:19:1)
at runCommand (C:\Users\aditi\AppData\Roaming\npm\node_modules\truffle\build\webpack:\packages\core\lib\command-utils.js:297:1)

我的环境版本信息：

• Truffle v5.11.5 (core: 5.11.5)
• Node v18.17.0

有没有大佬能帮我排查下问题所在呀？

备注：内容来源于stack exchange，提问作者Aditi Singh