Apple gift card purchases. After making a couple of purchases, it will say “Your purchase cannot be completed “

after making a couple of purchases with the Apple gift card, it locks me out saying Your Purchase Cannot Be Completed. I have contacted Apple Support via chat as well as phone calls. They do not have an answer. Ihave to wait 48 hours before I can make another purchase! This never happened in the past, just the last couple of weeks. I even use fingerprint I.D.