Nintendo has taken to Twitter to say that the issue with Android players starting Mario Kart Tour has now been resolved. Some players on Android devices weren’t able to make it past the smartphone game’s title screen and were greeted with a Support Code error of 806-6502. Nintendo says that this particular issue has now been resolved, but wouldn’t say what had caused the error in the first place. The team has taken the time to thank those who encountered the error for remaining patient while the issue was being worked on.
Nintendo resolves Android issue with Mario Kart Tour

It wasn’t just mario kart. The same thing happened for all android users in Dragalia Lost and Fire Emblem Heroes.
Please I had been getting that error message on my tablet since last year and had to switch to my phone cause it was the only way I could easily access it.
Now they need to fix the issue of using rubies to get characters only to get the same ones over and over with no chance of getting unowned characters