Infringement

Thanks for writing. Adobe Stock has partnered with many reseller partner sites which gives them access to display the Adobe Stock collection for their customers. If their customer purchases a product with your image, a license is bought directly through Adobe Stock. The difference between these sales and a sale originating at Adobe Stock is that it's a one time use only license. If another customer wants to use the same image through the API partner site then a new license must be purchased through Adobe Stock. 

The first two links you listed are API partners with Adobe Stock. I'm not familiar with the third site noted in the last two links. You may want to contact them and ask how they got your content. If you are non-exclusive it's possible they are an API partner with a different agency. 

These API partner sites dramatically increase exposure to your portfolio and increase any and all potential for earnings.

Best regards,

Mat Hayward 

I've forwarded your concern to the appropriate team.

EBQ