WEBI BEx Prompt LOV is not being displayed

I've 2 WEBI reports. Report 1 is based on PO Line item BEx query and Report 2 is based on G/L Line item BEx query. I'm using G/L account as prompt in both the reports by defining variable in BEx.

Report 1 (PO Line items) returns the LOV for G/L account when click on Refresh'.

Report 2 (G/L Line item) returns LOV as 'No values to display'

I ran Report 2 in BEx Analyzer and variable shows the LOV. We're on BI 4.1 SP 5.

I also checked the properties for G/L account in both the queries and they exactly match.

What could be the issue with G/L Line item for not displaying LOV for G/L account?

Thanks,

Milind