After spending several hours researching, reading XDA forums and downloading/checking firmwares, I decided last time to try full factory reset.

After wiping up the phone, I connected only to my wifi, did not put any SIM card inside. Then, when in the process to setup the phone, connected to my google and Samsung accounts which have US as location. During setup I put US English and language/keyboard and PST time settings. After downloading and installing Samsung Pay, I didn't allow it to access GPS/location.

Well, after all above, I was able to enter my US issued credit cards at Samsung Pay and activate them.