Family Sharing Purchase with Gift Card

I’m an adult member of family sharing where we share book purchases. I also play a couple of games and have in app purchases where I want to use my own funds. I redeemed an Apple gift card to my own Apple ID because I was informed by various sources that the funds from this card would be used first before defaulting to the family sharing visa. Unfortunately, my in app purchases still default to the family visa. Is there anyway I can use my own funds for app purchases?