Why do we have an Open Balance on customers in QuickBooks?

An open balance on customers in QuickBooks Online can occur when the follow pattern of events happens:

1. On 7/11/18, invoice #11339 is created with total amount of $0.00 in Printavo and exported to QuickBooks Online.
2. At 7/13/18, the total amount was changed to $1,395 in Printavo and is exported to QuickBooks Online. This is when the customer open balance got changed to: $1,395.
3. Subsequently, there was an update on the customer, that resulted in an invoice for an open balance amount of $1,395.

This issue can be corrected by not exporting invoices with a $0 amount.