How can I fix this error in discord.js bot?

I've made a discord.js reviews feature for my discord bot. I made it on a seperate file for ease of use, and everything works fine, no errors. But when I wanted to add a cooldown feature so no one just spams reviews, I get this message (I'm using replit so I can make it 24/7 online):

Error sending review: DiscordAPIError: Cannot send an empty message
    at RequestHandler.execute (/home/runner/Invite-Graphics/node_modules/discord.js/src/rest/RequestHandler.js:154:13)
    at processTicksAndRejections (internal/process/task_queues.js:97:5)
    at async RequestHandler.push (/home/runner/Invite-Graphics/node_modules/discord.js/src/rest/RequestHandler.js:39:14)
    at async ReviewBot.handleReviewCommand (/home/runner/Invite-Graphics/review.js:62:27) {
  method: 'post',
  path: '/channels/1137254692179689542/messages',
  code: 50006,
  httpStatus: 400
}

This is my code:

const { Client, MessageEmbed } = require('discord.js');
const config = require('./config.json');

class ReviewBot extends Client {
  constructor(config) {
    super();
    this.prefix = config.prefix;
    this.reviewChannelId = config.review_channel_id;
    this.cooldowns = new Map();
  }

  async start() {
    try {
      await this.login(process.env.TOKEN);
      console.log('Review Bot logged in successfully!');
    } catch (error) {
      console.error('Error logging in:', error);
    }
  
    this.once('ready', () => {
      console.log('Review Bot is ready!');
    });
  
    this.on('message', this.handleMessage.bind(this));
  }

  async handleMessage(message) {
    if (!message.content.startsWith(this.prefix) || message.author.bot) return;

    const args = message.content.slice(this.prefix.length).trim().split(/ +/);
    const command = args.shift().toLowerCase();

    if (command === 'review') {
      const cooldownTime = parseInt(config.review_cooldown_time);
      this.handleReviewCommand(message, args.join(' '), cooldownTime);
    }
  }

  async handleReviewCommand(message, review, cooldownTime) {
    const userId = message.author.id;
    const now = Date.now();
    const userCooldown = this.cooldowns.get(userId);

    if (userCooldown && now < userCooldown) {
      const remainingTime = ((userCooldown - now) / 1000 / 60).toFixed(1);
      message.reply({ content: `You need to wait ${remainingTime} more minutes before submitting another review.`, ephemeral: true });
      return;
    }

    const reviewChannel = this.channels.cache.get(this.reviewChannelId);
    if (!reviewChannel || reviewChannel.type !== 'text') {
      console.error(`Invalid or missing review channel with ID: ${this.reviewChannelId}`);
      return;
    }

    const embed = new MessageEmbed()
      .setAuthor(message.author.username, message.author.displayAvatarURL({ format: 'png', dynamic: true }))
      .setDescription(review)
      .setColor('#00FF00')

    try {
      const sentMessage = await reviewChannel.send({ embeds: [embed] });
      console.log(`Review sent by ${message.author.tag} in #reviews: ${review}`);

      this.cooldowns.set(userId, now + cooldownTime * 60 * 1000);
      setTimeout(() => this.cooldowns.delete(userId), cooldownTime * 60 * 1000);
    } catch (error) {
      console.error('Error sending review:', error);
    }
  }
}

const bot = new ReviewBot(config);
bot.start();

I wanted it to have a cooldown, so that when someone sends a review, they cant send another one until some minutes have passed. And an ephemeral message would be shown to that user and it will say they need to wait so and so time until they can review again. The cool down time will be determined in a config.json, which has the layout like so:

"review_cooldown_time":"5" (5 as in 5 minutes)

Here is the code link if anyone wants to see the full bot code: https://replit.com/@Cryptic1526/Invite-Graphics#review.js

I tried ChatGPT and Bard, those didn't help, tried researching online, still nada.

EDIT: Here is the code BEFORE I tried to add the cooldown: https://pastebin.com/59zxcR0z

Dennis, next time share versions, please. you are using version 12.53 in one and version 13 in the other. you need to migrate if you you are going to continue to use version 13 or downgrade your new code and abide buy the correct version of the API.