For me (amazon.de, EN language setting): Open app -> "More" burger menu botton right (three horizontal lines stacked on top of each other) -> Scroll down to "Customer service" -> Scroll down to search feature -> "Personal Information" -> #1. I think this is really just a webview to the same part of the website with a different design.

Takes a bit more tapping and scrolling than clicking on desktop, but that is more he fault of the smaller screen and how apps work I would guess.