Hello there, @rich-ridley1.
Consider me a detective on the case of this missing upload file. Can you clarify what kind of information you're uploading into QuickBooks Online using an Excel/CSV file? If possible, clarify where along the upload process the information isn't showing up at. For instance, if the data isn't appearing in the mapping screen that you work through before uploading, there will be different steps necessary than if the data was missing after the upload.
These guides on importing bank transactions and list items (Customers, Vendors, Ledger Accounts) can help with any basic questions you may have. Any information you can provide me will help to expedite the troubleshooting. Thanks for coming to the Community, I look forward to hearing from you again.
