Dye soak thru leather

[Dominicff]

Hello, I'm making some card holder and unfortunately dye soak thru the leather. It's veg tan leather about 1mm thick. What I tried to do to fix it is to dye on flesh side although I'm scared it could stains the business cards. 

 

Also, when sealing my work, I'm using either carnauba cream or super shene and in both products, it stains when cleaning with a damp cloth, even with two layers. It doesn't stain tho when using a dry cloth.

* I'm using eco flow dye, and eco flow waterstain seems to not go through the leather

 

Thanks for your help!