Call people back using genuine phone numbers. In today's world, it is easy for scammers to manipulate caller IDs and phone numbers. Therefore, you should never trust the name and number as it shows up on your phone. If you get a phone call from someone, ask them for their name and the company they work for, so you can call them back. Once you get off the phone, look up that company's information online and only call back legitimate numbers found on reputable websites.