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Why is Discord API returning error 405 for adding a slash command to a guild?

December 18, 2021

I’m currently making a bot in discord.js, and I’m trying to build a command handler ( for slash commands specifically). Unfortunately, whenever i run the code, it returns a 405 error from the discord API. here is the error:

DiscordAPIError[0]: 405: Method Not Allowed
    at SequentialHandler.runRequest (/home/ayman/Documents/Projects/image-bot/node_modules/@discordjs/rest/dist/lib/handlers/SequentialHandler.js:198:23)
    at processTicksAndRejections (node:internal/process/task_queues:96:5)
    at async SequentialHandler.queueRequest (/home/ayman/Documents/Projects/image-bot/node_modules/@discordjs/rest/dist/lib/handlers/SequentialHandler.js:99:20)
    at async /home/ayman/Documents/Projects/image-bot/src/main.js:35:5 {
  rawError: { message: '405: Method Not Allowed', code: 0 },
  code: 0,
  status: 405,
  method: 'put',
  url: 'https://discord.com/api/v9/applications/921468165576347658/guilds/545334770368774146/commands/undefined'
}

And here is the problematic code:

(async () => {
    try {
        if (process.env.ENV === "production") {
            await rest.put(Routes.applicationCommand(CLIENT_ID), {
                body: commands,
            });
            console.log("Commands successfully registered globally.");
        } else {
            await rest.put(Routes.applicationGuildCommand(CLIENT_ID, process.env.GUILD_ID), {
                body: commands,
            });
            console.log("Commands successfully registered locally.");
        }
    } catch (err) {
        if (err) console.error(err);
    }
})();

Is there any reason why this is happening? Thanks for any help!