如果收集器没有得到正确的答案，Bot就会崩溃

我制作了一个&scramble命令，该命令基本上会对一个单词进行加扰，并将其显示给人们猜测，30秒后，它将停止接受答案，并说出谁先答对了，这一部分工作正常，但当没有人答对时，机器人会因为没有返回某人而崩溃，给出错误TypeError: Cannot read property 'author' of undefined

module.exports = {
name: 'scramble',
execute(message, args) {
const Discord = require('discord.js')
let givenword = args.slice(0).join(" ");

function scramble(givenword) {
var word= givenword.split("")
n = word.length
for(var i = n - 1; i > 0; i--) {
var j = Math.floor(Math.random() * (i+1));
var tmp = word[i];
word[i] = word[j]
word[j] = tmp;
}
return word.join("")
}
scrambledword = scramble(givenword)
const embed = new Discord.MessageEmbed()
.setTitle('Scramble time!')
.setColor("RANDOM")
.setDescription("The word is: " + scrambledword)
.setFooter('You have 30 seconds to try and guess it, the first person to answer correctly ')
message.channel.send({embed});
message.delete()

const filter = m => m.content.includes(givenword)
const collector = message.channel.createMessageCollector(filter, { time: 30000 });

collector.on('collect', m => {
console.log(`Collected ${m.content}`);
});

collector.on('end', collected => {
if (collected.length <= 0) {
message.channel.send('Sadly it seems like no one has guessed the answer right... The word was ' + givenword + "!")
} else {
message.channel.send(`${collected.first().author} got the correct answer first! The answer was ${givenword}`);
}
console.log(`Collected ${collected.size} items`);
});


}
}