If you are unable to create an item, it is important to check the following.
An article must, if applicable, be linked to quality and / or colors and / or sizes. Only when everything is linked, is it possible to use this data with the article.
To check whether everything is properly linked, it is best to use article validation. There are always the records for every combination of the dimensions used in the article. So if you don't see any data, at least one of the data mentioned above must still be linked to the item.