Hello there, @maricela1.
I'm here to help share some information about the notify settings in QuickBooks.
At this time, we don't have the option to notify the admin user if another user is working on an invoice in QuickBooks. However, we do have an audit trail that lets you see exactly what changes were made and who made them. Let me route you to this article for more details: The Audit Log: What it is, how to use it.
It'd be nice if we have that notification in QBO. You can always send a suggestion to our developers so they can check into this and consider it adding to our future update. You can send feedback directly to this link: http://feedback.qbo.intuit.com.
I'll be here to help if you have additional questions about this access. Wishing you the best.
