Pag-IBIG Loyalty Card Plus

Hello, guys! I just received my Pag-IBIG Plus UnionBank card earlier. Does anyone know how to link it to the UnionBank app?

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I tried adding it, but the document only shows a 10-digit account number. The app seems to require a 16-digit card number. Where can I find it, or has anyone experienced the same issue?

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Thank you!