Why is my new variable product not appearing in my Web Store

You will not be able to insert a product that has duplicate sizes and colours.
You can only have one combination of size and colour for the Web Store to be able to add the product. This example below shows duplicates of the white in sizes 6,8, and 10

size colour ProductId SKU Code
 6 WHITE 135965 V7209066WHITE V720906
 8 WHITE 135966 V7209068WHITE V720906
 6 WHITE 134255 V7209066 V720906
 8 WHITE 134256 V7209068 V720906
 10 WHITE 134257 V72090610 V720906
 6 BLACK 136735 V7209066BLACK V720906
 8 BLACK 136736 V7209068BLACK V720906
 10 BLACK 136737 V72090610BLACK V720906
 12 BLACK 136738 V72090612BLACK V720906
 10 WHITE 135967 V72090610WHITE V720906