Report Designer Expression: Mark Items with Asterisks Based on Conditions

Hello everyone,

I'm trying to create a calculated field in the Report Designer, but it's not working as expected.
Could someone please help me?

What I'm trying to achieve is the following:

Depending on the warehouse location (SiteID) and whether the item is accredited (UsrAkkreditiert = True or False), I want to mark the items with different numbers of asterisks (*).

Each warehouse has its own rule:

• For internal warehouses (TESTSHH or TESTSNMS), only non-accredited items should be marked with a single asterisk (*).
• For external warehouses (EXTERNHH or EXTERNNMS), I want to mark:
  •   Accredited items with two asterisks (**),
  •  Non-accredited items with three asterisks (***).
• If the conditions don't match any of the above, the field should remain blank.

Any ideas why this expression isn’t working, or suggestions on how I can correct it?

Here is the expression I'm currently using:

=IIf(
    [SOLine.SiteID] = 'TESTSHH' Or [SOLine.SiteID] = 'TESTSNMS',
        IIf([InventoryItem.UsrAkkreditiert] = False, '*', ''),
    IIf(
        [SOLine.SiteID] = 'EXTERNHH' Or [SOLine.SiteID] = 'EXTERNNMS',
            IIf([InventoryItem.UsrAkkreditiert] = True, '**', '***'),
        ''
    )
)

Thanks a lot for your support!