Hello There,
Thanks for posting your query.
Reports scheduled via report builder will appear in the Schedule section under your Addin section for Report Builder in Excel itself. They won't be available when you login to see them in Analytics via a browser.
Do you see anything in the Report History section under Scheduled Task Manager?
You can have a maximum of 10 scheduled workbooks per Report Builder license. However, you can increase this number by subtracting from other licenses. To do so, go to Admin > Company Settings > Report Builder Reports.
See this Doc for more on this: Schedule Report Requests
Hope this helps!