Hi @Tejaswini Morey 

The last activity is gathered automatically for few individual products directly without any discovery solution. These include Exchange Online, Teams, One Drive, Power BI, Share Point Online, Viva Engage (formerly Yammer) 

Refer: 

ServiceNow SAM Pro determination of last activity date for M365 Subscriptions

Microsoft 365 License compliance and optimization support on ServiceNow SAM Pro

https://www.servicenow.com/community/sam-forum/there-are-miscrosoft-subscription-softwares-in-the-in...