Unknown:Input data for tag <Item.Variations.Pictures.VariationSpecificPictureSet[1].PictureURL> is invalid or missing. Please check API documentation.

When this error occurs in the listing or synchronization, the picture is abnormal;

1. First, check the picture in the datasheet, including the multi-variation picture. Check it if the format is incorrect or display abnormal.

2. When the picture link contains spaces, it can also appear in this error.

For instance：

https://www.lifekingdom.co.uk/PH/2018/UPH0012GY iPhone 6.jpg

This link contains spaces beside 'iPhone'. At this moment, this picture link is invalid. You should use '%20' to replace the space ，

The correct link should be like that:

https://www.lifekingdom.co.uk/PH/2018/UPH0012GY%20iPhone%206.jpg