Adjust PO -> error when confirming the PO

Hi all,

When i create a PO with one line, confirm the PO but then i change the PO-line (for example i change the quantity from 5 to 6), the system gives following error:

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Debugging the code is apparently not possible...

Can someone give me the explanation and th path to add a right ledger account?

Thanks a lot!

Frederik Vanhaelst