Direct query automatic update not working

Hello,

Previously I've published a report that uses direct query on an Microsoft SQL Server database and everything worked fine (the automatic updates are happening every 15min as expected).

However, I am now trying to publish another report using direct query on the same database and I only have the option to schedule the updates (like when I use import) in 8 different moments of the day.

Does anyone have a clue on what might be the problem? I need this report to be the closest to live as possible.