If you are using Method:CRM with QuickBooks Online, this article outlines why transactions numbers are empty.
If you are using Method:CRM with QuickBooks Online, this article will outline common reasons why transaction numbers would be blank after creating a transaction (invoice, estimate, sales receipt, etc.) and the steps to resolve this.
Either Method:CRM or QuickBooks will assign the transaction number. The first thing you need to do is verify which program it is.
If QuickBooks Custom transaction numbers are turned off, and you don't want Method to assign transaction numbers, then proceed to step 2.
By now, you have determined that Quickbooks should be assigning transaction numbers, but it is not. There are a few things you can check for this.
Open your transaction with the blank number. Is "Wait for Sync Approval" checked?
If the transaction is awaiting approval before syncing to Quickbooks, then this transaction is not in QuickBooks and Quickbooks cannot assign a number.
You must uncheck Wait for Sync Approval.
If this is unchecked but the transaction number is still blank, go on to the next section.
You should try and refresh your connection with QuickBooks. Please see our article on Reconnecting QuickBooks with Method:CRM.
If this does not help, please go to Step 3.
If none of the above has worked, then you should check to see if the transaction in question has a sync conflict.
If you have gone through these steps and still require assistance, please reach out to Method Support.