If you are trying uploading a logbook data loader but this is fetching back errors on the validation step:
Review the logbook validation messages.
If you are sure your template is correct, copy the data into a new spreadsheet, make the relevant changes, and upload again.
Check your logbook template name for any double spacing or special characters.
📌Note: If you have special characters in the logbook field headings, these would need to be changed to wording as the sheet will not validate with any double spacing or special characters.
If this still fails, raise a case and provide:
A copy of the sheet you are trying to validate.