Sales invoice posting with prepayments error

dear all,

we have a problem when posting an invoice using prepayment for sales module.

these are the scenario :

we created a sales order using prepayment. There are 2 prepayments on the sales order and created with different currency rate (our local currency is IDR). Prepayment invoice are already posted, sales shipment already created and there is no problem with that, but the problem come when we want to create the invoice for the sales order.

when we want to post it, there is an error message : “the G/L entry already created”.

we already run the debugger and when the system post realize gain/loss (currency difference) it using used entry no. so the error message appears.

i have no idea why the system use used entry no when post the realize gain/loss. i have try to recreated the transaction but using another scenario such as :

  • we used an item in sales order and prepayment are created with same currency rate

  • we used a g/l account in sales order and prepayment are created with different currency rate

both works fine.

for additional info, we use NAV 2009 R2 Indonesian Version

could anybody help me?

Thanks

Regards,

Yosa