How do I resolve 'App Licence Expired' error for Fortnite on iPad?

Hi, today I tried to do Fortnite update on my iPad, but when I press Fortnite or Epic games icon on screen it gave me these communicate. "App Licence Expired The licence for "Fortnite" has expired. To open the app, you must first resolve the issue." Then when I click resolve button iPad opens Safari with Epic games downloader and the instruction how to download. I've done everything what they said, buy i still can't open app. I've been talking with Epic support, but they told me that is problem with Apple and the recommend me to write here. Please, help me. It's my first Apple device.

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