This is a very weird situation from Quickbooks.
Basically, when you're doing something on the UI, Quickbook memorizes it.
MD is now trying to update the item and Quickbooks ask if you want to update the transaction as well (like price change for example)
The only way to fix this is to open the item in Quickbooks and update the item, you'll get the same question and have a chance to settle/remove the memorized transaction and then do a quicks sync.