Overview
Deleting or removing sessions will include engagement data (i.e. polls and Q&A) associated with the sessions.
Please Note: We are unable to restore any data that is permanently deleted. Please use caution when deleting data from the site, and archive or hide wherever possible. To keep a record of the data but hide the session instead, see the article on archiving sessions.
Step-by-step
1. Sign in as an Admin and click Manage Sessions
2. Select the sessions to be removed or check the box at the top to select all sessions and click Permanently Remove: 
3. To complete the removal, enter the Admin password and click Confirm: 
If you want to selectively remove data, (e.g. poll responses), see the Clear Data article.