Error when trying to amend a sales invoice - crashing MYOB

After speaking to MYOB, they are aware and the temporary fix is that stock has to be added to any item on the invoice that ended up with a zero balance. It will then let you amend the invoice

Hi FionaMiriam 

As has been indicated on this thread, we are aware of a situation where if the item does have a zero on-hand quantity and you are editing an invoice or bill for that item you will encounter a particular error message. 

If you are encountering that particular error, we would recommend an inventory adjustment to increase the item's stock on hand and the stock value. You would then be able to edit that particular transaction without the error occurring. Once that transaction has been edited, we would recommend recording another inventory adjustment to reduce the stock quantity and value back to 0.00. Please note: This is only to be used if you are needing to edit an already recorded invoice or bill, newly recorded invoices or bills are not impacted.

This should be noted that this is something that we are aware of occurring in the current software and have reported it to the required teams for further investigation for a future update. At this time, we don't have a timeframe for resolution.