Cannot purchase anything. Family sharing is enabled.

In my family, we have set up family sharing between our iPads. My father is the family organizer and i am a family member (adult). My father has set up a credit-card payment method and has enabled purchase sharing.

Now, I wanted to perform some in-app purchase. When I click on 'Purchase' in the app, it shows me the following message:

"Verification Required: Before you can make purchases, you must tap Continue to sign in, then verify your payment information."

When I click on 'Continue', it asks me the following:

"To continue on this device, verify at least one payment method. If you can't verify any payment methods, contact your family organizer."

When I click on verify, it asks me to enter the credit-cards CVV number.

Now obviously, I can't be given my father's card's CVV number. My father also tried sending me a gift card which I added to my Apple ID balance. I tried to use this, but it still gave me the same messages as above and eventually could not select the 'Apple ID' option.

I am also not able to edit my payment methods because the 'Edit' option is grayscaled.

My question is: How can I make the purchase without having to enter my father's card's CVV number and without having to disable family purchase sharing.