Coupon error: Choose variant

I am facing a coupon-issue.

When applying the coupon “2680” when buying a Pumie sten med h?ndtag, all I get is an error code: “Farve” er et p?kr?vet felt (which means “Color” is a requed field).

However is the product setup as a single product without variants, and furthermore is “farve”/color not set up as a product attribute.

Screenshot: https://www.dropbox.com/s/r00yfgnitxyguiy/Sk%C3%A6rmbillede%202015-05-23%2015.52.06.png?dl=0

Does anyone have an idea about what could be wrong?

Thanks in advance!

Emil

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