Hi Marc,
Based on this image, the first part of your report is Custom and the second is General (Excel understand there is no month 13)
This is more related to your date/time region settings.
The date format in my region is d/MM/YYYY, but I think your computer is set to YYYY-MM-dd.
You can check on Control Panel > Region:
One thing you can try to do is to select a different language when generating your reports, this you will give you a different result (e.g. English US, English GB).
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Paulo Mesquita
Spark NZ Trading
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