I have been looking around for a while now and it seems that all the ways to delete your direct messages on Twitter at once are outdated and do not work anymore. I was just wondering if anyone had found a current solution on how to delete all direct messages on Twitter at once.
As of now there is no official way to delete all direct messages at once. You have to use some third party apps.
You can give a try to this app Twitter DM Cleaner. The app will ask for access to your DMs.