Hello, @TamaraJ.

Thanks for joining this thread. Allow me to steps in and provide some information about the attachment list in QuickBooks Online (QBO).

Adding an attachment to customer or vendor profiles and their transactions helps organized the records. Currently, there isn't an option to sort or arrange the transaction list in QBO. 

For additional reference, you can check this article to learn more about the attachments in QuickBooks Online. 

Don't hesitate to leave a comment below if you have other questions about the list attachment. I'll be around to help.