I’m having a similar issue as well. I have the username, email, and nickname fields on my form. The strange thing is that the nickname saves when I register using my desktop and mobile phone but not on my laptop(all devices on the same network). I only detected the issue because a user registered and posted a comment stating that their nickname is not showing. For now I have the annoying task of updating the nickname manually for each new user by looking at the new user account email which displays the nickname correctly. I’m working on finding a solution but UM coding is so hard to trace with all actions and filters being used.