下面是您应该如何继续操作：将最后发送的消息存储在一个变量中，并使用它来更新内容。

if (cmd === 'fivemst') {
    let message = null;
    function updateMessageWithNewEmbed() {
        sys.probe('cfx.re', async (isAlive) => {
            if (isAlive) {
                embed = new MessageEmbed().setAuthor(
                    'FiveM System Status -  ',
                    'https://cdn.discordapp.com/attachments/1041091660316160032/1053741836725915818/82d62076a21ee0f408aa344403324efb5eb669cd.png',
                ).setDescription(`
                    ✅

                **All Systems Operational**
                `);
            } else {
                embed = new MessageEmbed().setAuthor(
                    'FiveM System Status - ',
                    'https://cdn.discordapp.com/attachments/1041091660316160032/1053741836725915818/82d62076a21ee0f408aa344403324efb5eb669cd.png',
                ).setDescription(`
                    ❎

                **Partial System Outage**
                `);
            }
            if (message) message.edit({
                embeds: [embed]
            });
            else {
                message = await message.channel.send({
                    embeds: [embed]
                });
            }
        });
    }
    setInterval(() => updateMessageWithNewEmbed(), 4000);
}