My `warn delete` subcommand is not working as expected, please help me out

[TechPro424]

I'm trying to delete a warn by using its `_id` property, but it is unable to find the warn, but when I console.log all the warns, it is there. Why am I unable to find the warn?

My warn.js command

const schema = require('../../models/welcome.js')
const { MessageEmbed } = require("discord.js")


module.exports = {
    name: "warns",
    description: "Warning system.",
    options: [
        {
          name: 'add',
          description: 'Warns a user.',
          type: 'SUB_COMMAND',
          options: [
            {
              name: 'user',
              description: 'The user to warn.',
              type: 'USER',
              required: true
            },
            {
              name: 'reason',
              description: 'The reason for the warn.',
              type: 'STRING',
              required: true
            },
            {
              name: 'evidence',
              description: 'The evidence for the warn.',
              type: 'STRING'
            }
          ]
        },
        {
          name: 'delete',
          description: 'Deletes a warn for a user.',
          type: 'SUB_COMMAND',
          options: [
            {
              name: 'user',
              description: 'The user whose warn to remove.',
              type: 'USER',
              required: true
            },
            {
              name: 'warn_id',
              description: 'The ID of the warn to delete (Can be fetched from the "warns list" command).',
              type: 'STRING',
              required: true
            },
          ]
        },
        {
          name: 'clear',
          description: 'Clear all warns for a user.',
          type: 'SUB_COMMAND',
          options: [{
              name: 'user',
              description: 'The user whose warns to clear.',
              type: 'USER',
              required: true
            }]
        },
        {
          name: 'list',
          description: 'Lists all the warns for a user.',
          type: 'SUB_COMMAND',
          options: [{
              name: 'user',
              description: 'The user whose warns to list.',
              type: 'USER',
              required: true
            }]
        },
    ],
    async execute(interaction) {
        const sub = interaction.options.getSubcommand(['add', 'delete', 'clear', 'list'])
        const member = interaction.options.getMember('user')
        const reason = interaction.options.getString('reason')
        const evidence = interaction.options.getString('evidence') || 'No evidence provided for this warn.'
        const warn_id = interaction.options.getInteger('warn_number')
        const date = new Date(interaction.createdAt).toLocaleDateString()

          let result = await schema.findOne({
          _id: interaction.guild.id
        })

        let user = result.warnings.find(u => u.userId === member.id)

        if (sub === 'add') {

          const embed = new MessageEmbed()
            .setDescription(`:white_check_mark: ${member} was warned.\nReason: **${reason}**\nEvidence: ${evidence}`)
            .setColor('RED')
            .setFooter(interaction.client.user.tag,interaction.client.user.displayAvatarURL({dynamic: true}))
          await interaction.reply({ embeds: [embed], ephemeral: true })

          let warnId;

          if (user) {
            let warn = {
            reason: reason,
            executorId: interaction.member.id,
            evidence: evidence,
            date: date
            }
      let warnNum = user.warns.push(warn)
      warnId = user.warns[warnNum - 1]._id
          console.log(warnId)
          }

        if (!user) {
          user = { userId: member.id,
          warns: [{
            reason: reason,
            executorId: interaction.member.id,
            evidence: evidence,
            date: date
            }] }
          result.warnings.push(user)
          warnId = user.warns[0]._id
        }

        let dm = 'Yes';

        try {
          await member.send(`You were warned in **${interaction.guild.name}** for the reason: **${reason}**.`)
        }
        catch(err) {
          dm = 'No'
        }
        console.log(warnId)
        if (!result.logChannelId) return
        let logChannel = interaction.guild.channels.cache.get(result.logChannelId)
        if (!logChannel) logChannel = interaction.guild.channels.fetch(result.logChannelId, {cache: true, force: true})

        const logEmbed = new MessageEmbed()
        .setTitle('Member warned!')
        .setColor('RED')
        .setDescription(`${member} was warned by ${interaction.member}.\nReason: **${reason}**\nEvidence: ${evidence}`)
        .setFooter(`DM: ${dm} | Date: ${date}`)

        await logChannel.send({embeds: [logEmbed]})
        await result.save()
        return
        }
        
        if (!user) {
          const embed = new MessageEmbed()
          .setTitle('No warnings')
          .setDescription(`This user does not have any warnings.`)
          .setThumbnail(member.user.displayAvatarURL({ dynamic: true }))
          .setColor('RED')
          await interaction.reply({ embeds: [embed], ephemeral: true })
          return
        }   

        else if (sub === 'delete') {
          console.log(user.warns)

          
        let warn = user.warns.find(warn => warn._id.toString() === warn_id)
        if (warn) console.log('YEs')

        if (!warn) {
          const embed = new MessageEmbed()
            .setDescription(`Invalid warn ID.`)
            .setColor('RED')
          await interaction.reply({ embeds: [embed], ephemeral: true })
          return
        }

        const embed = new MessageEmbed()
          .setTitle('Warning deleted!')
          .setDescription(`:white_check_mark: Warning for ${warn.reason} removed from ${member} by ${interaction.member}.`)
          .setFooter(`Warn ID: ${warn_id}`)

        await interaction.reply({ embeds: [embed], ephemeral: true })

        
        const newUserWarns = user.warns.splice((user.warns.indexOf(warn)), 1)
        user.warns = newUserWarns
        if (!user.warns.length) result.warnings.splice(result.warnings.indexOf(user), 1)

        

        if (!result.logChannelId) return
        let channel = interaction.guild.channels.cache.get(result.logChannelId)
        if (!channel) channel === interaction.guild.channels.fetch(results.logChannelId, { cache: true })

        const logEmbed = new MessageEmbed()
        .setTitle('Warning removed!')
        .setDescription(`A warning has been removed from ${member} by ${interaction.member}.`)
        .setFooter(`Date: ${date} | Warn ID: ${warn_id}`)
        
        await channel.send({embeds: [logEmbed]})
        }

        
        else if (sub === 'clear') {

          const embed = new MessageEmbed()
          .setDescription(`:white_check_mark: All warnings have been removed from ${member}.`)

          await interaction.reply({embeds: [embed], ephemeral: true})

          result.warnings.splice(result.warnings.indexOf(user), 1)

          if (!result.logChannelId) return
        let channel = interaction.guild.channels.cache.get(result.logChannelId)
        if (!channel) channel === interaction.guild.channels.fetch(results.logChannelId, { cache: true })

        const logEmbed = new MessageEmbed()
        .setTitle('Warnings cleared!')
        .setDescription(`All warnings have been removed from ${member} by ${interaction.member}.`)
        .setFooter(`Date: ${date}`)
        
        await channel.send({embeds: [logEmbed]})
        }

        await result.save()


        if (sub === 'list') {

        const embed = new MessageEmbed()
        .setTitle(`Warnings for ${member.user.tag}`)
        .setThumbnail(member.user.displayAvatarURL({ dynamic: true }))
        .setDescription('Use the warn number in the `/delwarn` command to delete the warning.')

          for (const warn of user.warns) {
            embed.addField((warn._id).toString(), `Reason: ${warn.reason}\nExecutor: <@${warn.executorId}>\nEvidence: ${warn.evidence}\nDate: ${warn.date}`)
          }
        await interaction.reply({embeds: [embed], ephemeral: true})
      }
    },
}

My welcome.js model

const mongoose = require('mongoose');


const schema = mongoose.Schema({
    _id: {
    type: String,
    required: true
  },
  welcomeChannelId: {
    type: String,
    required: true
  },
  welcomeText: {
    type: String,
    required: true
  },
  chatChannelId: {
    type: String,
    required: true
  },
  logChannelId: {
    type: String,
    required: true
  },
  ticketInfo: {
    type: {
      categoryId: {
        type: String,
        required: true
      },
      roleId: {
        type: String,
        required: true   
      }
  }
  },
  starboardChannelId: {
    type: String,
    required: true
  },
  warnings: {
    type: [{ userId: String, warns: [{
      reason: String,
      executorId: String,
      evidence: String,
      date: String }] }],
    required: true
  }
});

module.exports = mongoose.model('welcome', schema);

Please help me out, thanks in advance!