Yeah, the black screen is an ongoing problem I'm trying to solve. One thing you could help me is to try is to run my other game on my profile (aespa Tower) on pc to see if it works. It's a bit of a complicated issue because only some type of devices are affected so I can't properly debug it.
I'll look into the name change too! What browser do you use and does a white input bar appear at the bottom of the screen if you tap on the name?