Ok so I got it to work finally...first, I've been having problems to get it to work at walmart, lowes and other places using chip readers. So i went to the self checkout to avoid embarrassment from ignorant cashier and customers. First I chose credit card as my method payment from the self checkout cashier's screen. Then I hold my phone next to terminal "where you slide your credit card". First time failed and gave me Error card reading, then I hit ok on the cashier machine screen, and tried again with hitting retry button on my Samsung screenot. Voila worked perfectly.
So what I found out is, all the stories that do chip credit card, you have to do the same method to get it to work...
Btw at the two times I held my phone next to the terminal for about 8sec "until the terminal peeps". If you remove the phone fast, it won't go thru....
Good luck guys. And if the cashier says "oh that's apple pay" scream in their faces and tell them NO, IT'S SAMSUNG PAY MF lhfh