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Hello ursus wolffheim,
Welcome to Microsoft Q&A forum.
Since this is a public forum, we will hide your personal identifiable information, and I have sent that image of yours containing your personal identifiable information in a private message so we can work together to resolve the issue. Also, please check your private message in case you want to share another screenshot to avoid leaking your PII by click on the Private Message button as show below.
As I checked, FilmForth is a third-party apps that is free to download on the Microsoft Store. I also see that you will have an option to buy premium for that apps on the Store as well. While the transaction and invoice will be made on the Microsoft Store, the license itself it monitored by the app developer. So in this case, please try to contact their support to see if they can help you with the license status. Thank you for your understanding.