The sync of an invoice from Autotask to QuickBooks Online is failing, and 'ERROR' is appearing within the Autotask Invoice Number field. You see the following output in AppConnect:
"Error creating the QuickBooks invoice for Autotask invoice ID _____ and account _____. Reason: There was an error. 400 Duplicate Document Number Error Duplicate Document Number Error : You must specify a different number. This number has already been used. The invoice number for Autotask invoice id _____ and account _____', was set to 'ERROR' in Autotask."
- Datto Autotask PSA
The custom transaction numbering option is enabled in QuickBooks Online, and the application is having difficulty assigning the 'next' invoice number because it's colliding with a number that is already in use.
To correct this behavior, turn off custom transaction numbering in QuickBooks Online by performing the following steps:
- In QuickBooks Online, select the tools icon in the top right-hand corner.
- Select Accounts and Settings.
- Select Sales from the left-hand menu.
- Edit the Sales form content section.
- Disable the Custom transaction numbers setting.
- Attempt the sync operation again.