ME2N - Open Invoice report inconsistent

Hi Experts,

I have a strange case here -

We have a service PO (Qty - 24 Hrs / Amt - 100 $) for which SES was posted for full Qty/Amt. Invoice was posted for full Qty but less amount (say 98 $).

This PO appears in the ME2N report for selection parameter RECHNUNG (Open invoice) with 'Still to be invoiced' amount as '0 $'. Please help.

Regards,

Akash