My wife is getting Phishing phone calls every 15 minutes

According to Recognize and avoid phishing messages, phony support calls, and other scams - Apple Support

Scammers may spoof legitimate company phone numbers and use flattery and threats to pressure you into giving them information, money, and even iTunes gift cards. If you get an unsolicited or suspicious phone call from someone claiming to be from Apple, just hang up.

You can report fraudulent tech support calls to the Federal Trade Commission (U.S. only) at www.ftccomplaintassistant.gov or to your local law enforcement agency.

Personally I deal with it just by turning in Settings > Phone > Silence Unknown Callers. See: Detect and block spam phone calls - Apple Support

if that person impersonates apple here's what you can do: https://support.apple.com/en-us/HT204759

if that person impersonates others you can block the phone number instructions to do so are provided in the link

You could try the FCC, but maybe better to inform your congressional reps and senator, pragmatically.

In the unlikely event that the calls are using the same number, block them.

If this isn’t a number where you need ro answer unknown numbers, disable ringing for all unknown callers.