Fix Power BI Drillthrough Report Interaction

Title: Drillthrough Filter Not Syncing Properly Between Main and Sub Reports in Power BI

⸻

Question:

Hi all,
I’m trying to replicate an SSRS-style drillthrough report setup in Power BI. The structure is:
• Main Report: High-level summary with Day_No, Report_Type, Campaign_Type, etc.
• Sub Report: Detailed breakdown filtered by DayRange (text), which is derived via relationship from Day_No (integer).
• I added DayRange as a drillthrough field in the sub report and am passing values from the main report.

⸻

What’s Working:
• Drillthrough triggers correctly only when I include DayRange or Day_No directly in the main report visual (which I don’t want to do).
• When I right-click the value, it shows the correct target report.

⸻

What’s Not Working:
• If I remove Day_No or DayRange from the main visual and move them to filters, the drillthrough option disappears.
• In the sub report, even though the drillthrough field (e.g. DayRange = '3 Days') is correctly passed, the slicer still shows a previously selected value (e.g. Over 15 Days).
• I have DayRange in a slicer in sub report with Single Select ON, but it still shows multiple options when drillthrough happens.
• I’ve tried dummy measures, hidden columns, etc. Nothing works consistently.

⸻

What I Want:
• How can I:
1. Enable drillthrough without having to show DayRange or Day_No in the visual itself?
2. Make the slicer in sub-report respect the drillthrough filter value?
3. Avoid showing duplicate or prior slicer values?

Any help, DAX magic, or setup hacks are welcome
Thanks in advance!