To archive a message from an inactive member on the mobile app, you'll just need to follow these steps:
1. Log into the app with your email address and password
2. Tap 'conversations' along the bottom bar
3. Locate the messages that you would like to archive and hold down your finger on this
4. A message will then pop up asking if you 'no longer need this message?
5. Tap 'OK' and this will archive the message
Currently this feature is not available on our desktop site, but we're working on it! By archiving messages on the mobile app, this will sync up with your inbox on the desktop site. If you archive a message on the app, it will then show in your 'archived' folder on the desktop site.