how can i get my credit card out of my iphone SE???????

I tried getting my old credit card out of my iphone and it wont let me i try canceling all of the payments that i have and it wont work now i want my samsumg cause you dont have these stupid problems samsumg you put delete old and done simple but iphone call apple for help cant get my credit card our and put a new one ughh everything is so hard apple why wont you make a samsumg update but not everyting is like samsumg