I am having the same issue. Been using QBO for a year and when I would create a invoice I could click on attachment and see all the receipts I had scanned in the QB IOS app. I would simple click on the ones I wanted to add. Worked perfectly.

Now today I am creating a new invoice and click on attachment I am only giving option to located files on my hard drive.  I have tried different computers, I have cleared my cache, I have also tried Chrome, Firefox, & Safari. All same issue.  Also I do see all the attachments I have scanned on the QB IOS app if I go to settings and attachments.