Row level security Help

The first consideration is going to be your model.  Right now you are filtering Invoice based on Country and Department separately.  This being that your invoice record must have some ID that links to Country and another ID that links to Department.

When you turn on the inactive relationship, Power BI will ignore the direct link of Country & Invoice and apply all country filtering via Department.

From a row level security perspective, which direction do you want Row Level security to filter via?  Do you want Country to filter invoice directly, or department?  I cannot be both.

Once you have made that choice, modify your relationships to match your choice above, then row level security should work.