title: Bot is not assigning roles. I am getting error missing permissions
body: <p>I am getting error when someone joins. I created a bot for college to assign a role according to their names. But I am getting error of Missing Permissions. Below is error which i am getting. Help me with it.
  (node:6660) UnhandledPromiseRejectionWarning: DiscordAPIError: Missing Permissions
      at RequestHandler.execute (C:\Users\hamza\Desktop\bot\node_modules\discord.js\src\rest\RequestHandler.js:170:25)
      at processTicksAndRejections (internal/process/task_queues.js:97:5)
  (node:6660) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a 
  catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag <code>--unhandled-rejections=strict</code> (see <a href="https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode" rel="nofollow noreferrer">https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode</a>). (rejection id: 1)
  (node:6660) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.</p>