I'd be happy to provide information and help you resolve your issue in uploading receipt photos in QuickBooks Online (QBO).
To begin, QBO doesn't recommend uploading receipts with sensitive or personal information, like credit card numbers and government identifiers.
Additionally, QBO supports PDF, JPEG, JPG, GIF, and PNG images. If you have a newer iPhone or iPad, your images might be in the HEIC format. You can convert HEIC images to a compatible format.
Moreover, After checking and verifying the photo format and information, you can try to upload it again. However, if it still doesn't work, let's clear the cache or use another browser to upload.
After clearing the cache, make sure to restart your browser. This helps refresh website preferences that might be causing problems when you use QuickBooks.