how to fix cannot read properties of undefined (reading 'push') in mongodb with djs

Question

const { Client, CommandInteraction, EmbedBuilder, Permissions, ApplicationCommandType } = require("discord.js");
const { Formatters } = require('discord.js');
const blacklistedWords = require("../../Collection/index.js");
const Schema = require('../../models/blacklist.js')
module.exports = {
    name: "blacklist_add",
    description: "add a word to blacklist so that the members of the server cannot use the word",
    userPerms: ['Administrator'],
    type: ApplicationCommandType.ChatInput,
    options: [{
        name: 'word',
        description: 'word to be added to the blacklist',
        type: 3,
        required: true
    }],
    /**
     *
     * @param {Client} client
     * @param {CommandInteraction} interaction
     * @param {String[]} args
     */
    run: async (client, interaction, args) => {

      const sword = interaction.options.getString('word');
      console.log(sword)
      const word = sword.toLowerCase();
      const guild = { Guild: interaction.guild.id }
      
      Schema.findOne(guild, async(err, data) => {
        if(data) {
          if(data.Words.includes(word)) return interaction.followUp(`The word already exists in the blacklist did you mean to remove it if so please use /blacklist-remove ${word} to remove the word from blacklist`)
          data.Words.push(word)
          data.save();
          blacklistedWords.get(interaction.guild.id).push(word);
        }else {
          new Schema({
            Guild: interaction.guild.id,
            Words: word
          }).save();

          blacklistedWords.set(interaction.guild.id, [ word ])
        }
        const embed = new EmbedBuilder()
        .setTitle('<:donetick:951395881607893062> Blacklist system')
        .setColor('GREEN')
        .setDescription('Word added- A new word has been added to the blacklist')
        .addField('Word', `${word}`, false)
        .addField('How do I remove the word from the blacklist?', `/blacklist-remove ${word}`, false)
        
        interaction.reply({ embeds: [embed] })
      });
    },
};

this is the code but it used to work with djs v13 idk now why is it giving this error the error image in console

can you please help I am new to djs v14 so I think that is an error caused by upgrading to v14 correct me if wrong