add a role to a user discord.js

Question

I am trying to make a command that gives a role to a member after I type power. I already have a mute command, and that one works completely fine, But if I copy that code and change the name of the command and the role it has to give, it gives the error:

TypeError: Cannot read property of 'roles' of undefined

my code is:

if(message.content.startsWith("power")) {
    let role =  message.guild.roles.cache.find(r => === "Role_ID");
    let member = message.mentions.members.first();
    member.roles.add(role)
  }

Answer 1

You can try:

if(message.content.startsWith("power")) {
    let role =  message.guild.roles.cache.find(r => === "Role_ID");
    let member = message.mentions.members.first();
    member.addRole(role)
  }