I am assuming that you have paid the fee twice? Call USCIS and ask if you can get one of the apps cancelled and get your money back. You should do this as soon as possible. Even if you can't get the money back, you should get the app cancelled to avoid any interference and delays this may cause.

Nonetheless, if you don't show up for your biometrics, they will consider the case abandoned. So you can choose to not show up to one of your appointments and they will cancel that case. No need for you to panic.

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