I see these ads on FaceBook and report them to FB when I see them. To report, tap the three dots at the top right of the ad, then select Report. Follow the prompts from there.
Please understand that Apple cannot control the ads FB chooses to display. But we can do our part by reporting them to the company showing the ads.

You can also report scam apps to Apple. To do so,
Reporting a scam app from the App Store
Starting iOS 15, you can report a bad app within the App Store on your iPhone itself. This is what it looks like:
- Open the App Store on your iPhone.
- Locate and tap on the app you want to file a report against to access its description page.
- Scroll to the Information section and tap Report a Problem under it. You will be redirected to Apple’s Report a Problem webpage.
- Sign in with your Apple Account.
- Tap the drop-down menu icon next to the I Would Like To text and choose an appropriate option: Request a Refund, Report a Quality Issue, Report a Scam or Fraud, Report Offensive, Illegal, or Abusive Content. Then, hit Next.
- Now, tap the drop-down menu icon next to the Tell Us More text and select one of the available options.
- Describe your issue and hit the Submit button. Apple will confirm that your report has been submitted.