How to Delete a Conversation/Private Message
There is no limit to the number of conversations you can have. You can keep them indefinitely. If you choose to have one no longer displayed to you within your conversations, click on the Kebab menu (three vertical dots) to the far right of the Star at the top of the conversation. Select Leave.
Once you leave a conversation, we cannot restore your access to it unless you are invited back to it.
You can do the following for leaving conversations in bulk (full page).
Open your conversation box. Add a checkmark next to the conversation title.
That will open a drop menu near the bottom. Add a checkmark to Select All.
Although you can add checkmarks next to each conversation, a drop menu near the bottom will appear once you select any. Click Choose action. Add a checkmark to Select all if you want to leave conversations in bulk (such as a full page).
Click the drop-down menu next to Choose action and select Leave conversations. Click Go.