We already took a look at this problem. But we don't have any clue of what's going on. You say, that he recreated his account with the same mail as before. But there's only one KirisuKuro member registered. And this is since 17.12.2018. We do have another registration with the name Kirisu, but with a totally different mail address. So either you want us to waste a lot of time or he didn't tell the truth and he's missing something. Ask him, with which mail address he registered before. I can tell you, if it is the right address or not. The IP address of both Kirisu accounts indicate, that it was probably made from the same internet connection. So he actually made two accounts which can count as multiaccounting instead of asking staff for help before doing any action on your own.
Maybe he's also available via Discord so we can talk/write to him directly. Ask him for his Discord name (or maybe you know it on your own).