Can I just tell you that after I sign in, I stay signed in until I clear my cookies. This might not work with Brave because it blocks cookies. That's why I stopped using Brave. If it is another browser, you might have it set to automatically delete cookies when you exit the browser. It is related to your browser in some way. Right now I am using Google Chrome and I didn't need to sign in. I have gone to Medium several times in the last few days without having to sign in. I just go to Medium and I am already signed in.
I'm a geek. So, let me know if I can help in any way. I love helping people with computer problems. I frequently answer questions at Microsoft Community and I have used computers since probably before you were born. Just reply back.
BTW, I started looking for tags with a larger number of followers whenever I write my stories now. For instance, if you start to write tech and see that it has 9K followers but technology has 100K followers, I choose technology. Can't say that it has helped monetarily but at least I know that more people will see my writing if they search for my tags.