Discord Bot how to fix error?

Question

Node.js

The code:

client.on('message', msg => {
    if (msg.content === '!role') {
        let nickname1 = msg.author.nickname

        if(nickname1.startsWith(`[Discord]`)) {
            message.channel.send(`+тег`)
        } else {
            message.channel.send(`-тег`)
        }
    }
})

Mistake:

if(nickname1.startsWith(`[Discord]`)) {
                     
TypeError: Cannot read property 'startsWith' of undefined

Answer 1

- let nickname1 = msg.author.nickname
+ let nickname1 = msg.member.nickname