I literally have to keep a text file on my phone with peoples names. I have exceptional visual and spacial memory, but names just slip through like sand through

I literally have to keep a text file on my phone with peoples names. I have exceptional visual and spacial memory, but names just slip through like sand through a sieve. With the text file, I just have to recall on roughly which line the name was and I am able to recall it. I have no idea why or how this works, but it does. I did try to keep a "Mental" list, but that just does not work, I need to type it in or write it on a piece of paper for it work.