Can not read properties of null (reading 'username')

Question

I'm trying to find a user by id but its erroring.

Here is my code:

module.exports = {
  name: 'whois',
  execute: (client, message, args) => {
    const userId = args[0];
    const member = message.guild.members.fetch(userId);
    message.reply(`Thats ${member.user.username}!`);
  }
}

Answer 1

The cause of the error is due to the fact you're not awaiting the fetch returned from <GuildMemberManager>#fetch.

Change your code to the following:

module.exports = {
  name: 'whois',
  execute: async (client, message, args) => {
    const userId = args[0];
    const member = await message.guild.members.fetch(userId);
    await message.reply(`Thats ${member.user.username}!`);
  }
}

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