Error
Parent Reference Invalid : This selection can only be a Category.
Cause
If Categories are enabled in QuickBooks Online, then all parents of a multi-level product mapping MUST be a product Category and the lowest level MUST be a Product.
Resolution
The “Product ID” field on the Procurement > Products list in ConnectWise PSA will map to the “Category” and “Name” fields (separated with a colon “:”) on the Company > Lists > All List > Products and Services screen in QuickBooks Online. If a Product in ConnectWise PSA does not exist in QuickBooks Online, it will be created automatically by Gozynta Mobius.
Please note, however, that the Product Category will not be created and must already exist in QuickBooks Online.
Please rename your product in the "Product ID" Field in ConnectWise PSA to one of the following formats:
Category Format: Category:Item
Example: Cables:10ft cat6
Sub Category Format: Category:SubCatgory:Item
Example: Hardware:Cables:10ft cat6
Please review the following articles for additional information