The date format is not ISO-compliant. For help with formatting, see http://sellercentral.amazon.co.uk/gp/help/30621
This error occurs when you provide dates that are not in the standard ISO-compliant format.
As an example, February 29, 2008, 1:10:30 p.m. in Seattle should be expressed as:
OR simply: 2008-02-29
The ISO standard is based on Greenwich Mean Time (GMT). If you're in the Pacific Time Zone, you are 8 hours off GMT (7 hours off GMT in Daylight Savings). This is indicated by the "-8:00" in the formula above. If you're in the Eastern Time Zone, you are 5 hours off GMT (4 hours off GMT in Daylight Savings).
One common reason why this error occurs is:
You entered the date correctly in an Excel-based template and Excel reformatted your date.
If you are using Excel to manage your data, you can format your date columns as text to prevent Excel from automatically reformatting them. To do this:
Go to the Format tool on the shortcut menu and choose "Cells."
On the Number tab, select "Date."
Choose "Text" to format numbers as text.
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