u have to reset your entire iPhone back to factory as if you were giving it away. Then set the phone up again by signing into your App Store. Because u did the reset they no longer have your previous data to say that there is a disabled account
I encountered the same problem and to be honest NOTHING helped me. I already contacted brawl stars support (on my other phone via in-game chat, as it is only method you can contact them) several times and they give me only vague answers and close conversation.
This seems something to me from within brawl stars. Or doe you see a popup that your account is disabled in the App Store and itunes? If not, it is something from within brawl stars I am afraid, see if you can reach their support via the web
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