For some reason quite often when i do a receipt of goods invoice a few days later the invoice shows for $0 with lines "0" invoiced. I do multiple invoices in batches and i always make sure that the quantity being invoiced matches what we received and are being billed to the exact penny , so i'm not sure why this happens to only a few ? 

Does anyone know why this happens ? And how can i fix the ones that are already batched out ? 

Thank you, 

Yessenia