Avoiding Fraudulent Phone Calls?

If you have a smart phone, block calls/texts from anyone you do not recognize. This will slow down the calls a lot. Be sure you're on the do not call list. If theres anything that isnt absolutely necessary or looks suspicious, delete it & it will also free up space on your phone. A good security app will help you block hackers from your phone, as well as detect any malicious apps that may already be on there. On Android devices there are plenty of apps available on the Play Store & keep all apps up to date. Dont download questionable apps. Clear your internet history/cache/cookies often. Don't store passwords on your device. Do not reuse a password you already have. It should be 12-16 characters long. The password must be a random combination of letters, numbers, & symbols. Always use complex passwords. Keep your phone w/ you at all times. Always use a pass code lock. Enable two-factor authentication. Fingerprints/face ID. Only give your PII when necessary. Turn on tracking. Don't use public Wi-Fi without a virtual private network (VPN). Report fraud to businesses. Dont even click on a link that you get from a potential phishing scam, as you should interact with them as little as possible. If you suspect an email you received is a phishing scam, you can report it: reportphishing@apwg.org. Be cautious with Save my information for next time. Many websites now store personal banking or credit card information to make it easier for you to buy a product or to pay a bill in the future. Although convenient, if your account is hacked, your payment information is more easily available to hackers. Ensure any website where you enter your financial information is secure (the websites URL should start with https://remember that the s is for secure), that your password is unique to that account, and that you log out once you are done. Sign up for account alerts. Many email providers and social media websites allow users to sign up for an email or text alert when your account is accessed from a new device or unusual location. These email or text alerts can quickly notify you when an unauthorized person accesses your account and can help minimize the amount of time an unauthorized user has access to your information.

If you receive such an alert, login to your account immediately and change the password. Check these emails closely, however, since malicious phishing emails often mimic these kinds of alerts.Notify others. When appropriate, contact your friends and family and make them aware your device or account has been hacked. Hackers may try to gain access to your email contact list, and send emails from your account. Notifying friends and family that your account has been hacked, and instructing them not to open urgent or strange emails, click on suspicious links, or download attachments that seem to come from you may help protect their accounts from hackers. Watch out for other users. People often are not immediately aware that their email or social media accounts have been hacked. In fact, many people only learn of the problem when friends or family contact them about a suspicious email or message from their account. If something doesnt seem right about a persons email or social media account, it is possible the account was hacked. Do not respond to any emails or messages you receive, but contact your friend or family member directly and tell them about the problem. Monitor financial accounts. If a hacked account contains financial information, contact your bank or credit card company immediately, letting it know that your account may be compromised. Your bank or credit card company may issue you a new card or account number. Be sure to monitor activity on the account for any fraudulent transactions. In some cases, hackers may have obtained your information, but will not use it right away. If you are not issued a new card or account number, you should monitor your account for an extended period. Hacking is a crime & should be reported:
FBI-www.fbi.gov
www.ic3.gov/
FTC:www.consumer.ftc.gov
Run a full system scan to check for malware. Reboot your phone every week by turning it off & then back on. Factory-reset your phone.

I'm sorry but it does not sound like you are talking about the type of calls that people receive all the time - that can be stopped by blocking numbers etc.
You will have to take your phone in person to an official authorized dealer or corporate office and explain your problem.
You can locate these offices on Google, just be sure the office/store is an authorized dealer.

Be sure to talk to a supervisor. If you do not feel satisfied with their answers, then acquire the address of the corporate offices and send your correspondence to them but be sure to provide the name and address of who you talked with.