Hey AYA!
Thanks for taking an interest in Skullgirls Mobile! It seems like you have a version of the game that's not supported. I want to clarify that we cannot support builds of the game that are out-of-date, or were obtained outside of Google Play or iTunes Appstores. Secondly, the May 25th release is a Hard Launch for North/South America, Europe, Australia, New Zealand, and the Philippines. Japan will not apart of the May 25th release. However, we're hoping to launch in Japan, and other Asian territories, later this year.