Can't register my Nesica card with Groove Coaster?
Update 11/29/2022: I was finally able to register my card just now. Left out the underscore and used the full width characters and was able to register. I think I lucked out because either my account finally timed out or I tried playing after an update. When I played the game, it asked if I wanted to migrate my account and was able to change my name then. Though being in PST and playing later in the night, it seemed to require a date in JST so had to pick the date after when I played.
Update 07/30/2022: tried again after over 2 weeks since I last tried at a different arcade. The Groove Coaster machine there was online and recognized my card and got my progress, but trying to register still did not work. I'll have to look out for other games that I could use the card on and try my luck with those. I think trying to link my card with just Groove Coaster is a lost cause at this point.
A nearby arcade has a Groove Coaster machine that's connected online and sells Nesica cards. I have been able to use it in the game and it seems to have recognized and saved my progress so all seems good.
However when I try to register my card with my account, I cannot complete registration since because I get "The card name is invalid" (カード名が不正です) error. In the game, I registered with the name "Appl_Jax" and I fear the underscore is causing problems.
How can I register my card now?
As far as I can tell, I cannot change the name associated with the card in the game, and the site just refuses to accept my card info. Or perhaps I'm going through the wrong settings? I tried using different underscore characters, just in case it only recognized a particular one, I tried changing the date to what is technically tomorrow for me and that didn't work either. The name itself seems to be correct because if I try any other name, I get a "Could not authenticate." (認証できませんでした。) error. I guess I need to wait two weeks for the system to forget about my info and try again?
Native Japanese here.
There's nothing wrong with using underscore, but you have to use full-width character (which is, I believe, no way to type it in English keyboard).
Try it with "Ａｐｐｌ＿Ｊａｘ" and see if it succeeds.