Common reasons for upload failures are incorrect file format, @Pineapplenails.
Ensure you follow the steps in formatting CSV files in Excel to get bank transactions, as CSV file formats vary by bank. Some may not be compatible with QuickBooks (QB) if they don't follow the required structure.
Align the upload process and file format with QB, noting that menu options and account names may vary. QuickBooks only imports CSV files in either a 3-column or 4-column layout. Choose the format that matches your bank’s export file.
- CSV (.csv)
- Quicken (.QFX)
- QuickBooks Online (.QBO)
- Microsoft Money (.OFX)
- Text files (.TXT)
If the issue persists, I recommend troubleshooting by clearing the cached data as this can improve performance in QuickBooks. If this same thing happens, you can switch to other supported browsers so we'll know if this only happens to the one you use or not.
On top of that, you can read this article about how categorising transactions ensures accurate tracking: Categorise transactions in QuickBooks Self-Employed.
Let us know if you have any other questions about uploading CSV transactions or QBSE-related concerns, feel free to comment below.