A fraud protection hold is sometimes triggered on customers by their own credit card company when they try to make a purchase from the Apple App Store. Apple maintains the App Store and processes all charges. For your security and privacy, only Apple knows your purchase, payment, and credit card information.
If an App Store charge is declined, Apple will usually resubmit the charge again. In certain circumstances where the charge is suspected of being fraudulent, the credit card company may continue declining the charge and you may need to change the credit card on file with the App Store. Please see this Apple support article: https://support.apple.com/en-us/108095
We are unable to assist with this as it is a transaction between your bank or credit card company and Apple and we have no insight into your purchase history or credit card information.