Cannot read properties of undefined 'on' - discord.js

Question

It gives me this error with the following code
TypeError: Cannot read properties of undefined (reading 'on')
at C:\Users\mihai\Desktop\Eli_4.0.0\handlers\loadSlashCommands.js:21:34
at Array.forEach ()
at module.exports (C:\Users\mihai\Desktop\Eli_4.0.0\handlers\loadSlashCommands.js:11:37)
at Array.forEach ()
at new MainClient (C:\Users\mihai\Desktop\Eli_4.0.0\nanospace.js:68:88)
at Object. (C:\Users\mihai\Desktop\Eli_4.0.0\index.js:2:16)
at Module._compile (node:internal/modules/cjs/loader:1105:14)
at Object.Module._extensions..js (node:internal/modules/cjs/loader:1159:10)
at Module.load (node:internal/modules/cjs/loader:981:32)
const { readdirSync } = require('fs');
const { PermissionsBitField, Routes } = require('discord.js');
const { REST } = require('#discordjs/rest');
const delay = require('delay');
const chalk = require("chalk");
module.exports = async (client, message) => {
const data = [];
let count = 0;
readdirSync("./slashCommands/").forEach((dir) => {
const slashCommandFile = readdirSync(`./slashCommands/${dir}/`).filter((files) => files.endsWith(".js"));
for (const file of slashCommandFile) {
const slashCommand = require(`../slashCommands/${dir}/${file}`);
if (!slashCommand.name) return console.error(`slashCommandNameError: ${slashCommand.split(".")[0]} application command name is required.`);
if (!slashCommand.description) return console.error(`slashCommandDescriptionError: ${slashCommand.split(".")[0]} application command description is required.`);
client.slashCommands.set(slashCommand.name, slashCommand);
data.push({
name: slashCommand.name,
description: slashCommand.description,
type: slashCommand.type,
options: slashCommand.options ? slashCommand.options : null,
default_member_permissions: slashCommand.default_member_permissions ? PermissionsBitField.resolve(slashCommand.default_member_permissions).toString() : null
});
count++;
}
});
client.logger.log(`Client SlashCommands Command (/) Loaded: ${count}`, "cmd");
const rest = new REST({ version: '10' }).setToken(client ? client.config.token : process.env.TOKEN);
(async () => {
try {
client.logger.log('Started refreshing application (/) commands.', 'cmd');
await rest.put(Routes.applicationCommands(client ? client.config.clientID : process.env. CLIENT_ID), { body: data });
client.logger.log('Successfully reloaded application (/) commands.', 'cmd');
} catch (error) {
console.error(error);
}
})();
await delay(4000);
console.log(chalk.white('[') + chalk.green('INFORMATION') + chalk.white('] ') + chalk.green('Command Slash ') + chalk.white('Events') + chalk.green(' Loaded!'));
};