Hello @Gavin Till,
Welcome to the LastPass Community!
I will like to know if you follow these process: https://support.lastpass.com/s/document-item?bundleId=lastpass&topicId=LastPass/UAC_Reporting_Generalreports_UserActivityEvents.html&_LANG=en.
I'll be waiting for your reply.
Kind Regards,
Alejandra
LastPass Support