Role Member (JS) Database (Enmap)

const Enmap = require("enmap");
let db = new Enmap({name: "rolemembers"});
client.on("ready", async () => {
  db.ensure("data", {
    role: null,
    channel: null
})})
client.on("message", async message => {
  if(message.content.startsWith(prefix + "set")) {
  var args = message.content.split(" ").slice(1)
  if(!args[0] || !args[1]) return message.channel.send("> **Use:** " + prefix + "set [role-id]  [voice-channel-id]");
    let ro = message.guild.roles.get(args[0]);
    if (!ro) return message.channel.send("> **I can't find this channel!**")
var ch = client.channels.get(args[1])
    if (!ch) return message.channel.send("> **I can't find this role!**")
    await db.set("data", {role:args[0], channel:args[1]})
    await message.channel.send("> **Done..**:white_check_mark:")
  }
})
client.on('guildMemberUpdate', member => {
    let data = db.get("data");
 if(data.role != null && data.channel != null) {
  var role = member.guild.members.filter (m => m.roles.get(data.role))
  member.guild.channels.get(data.channel).setName(`members: [${role.size}]`)
 }
 });