Phishing attempts can arrive by phone as well as email. A variety of phone scams, which have been reported at Brown and posted to the Phish Bowl, will give you a good idea of some of the more typical ones.
If you receive a suspicious call, whether from a number you do not recogize, or a caller who attempts to scare or force you into an action that doesn't seem quite right, do not engage them and terminate the call. We also recommend adding that number to your blocked caller list, which is typically done by selecting it from the call log and then marking it to "block this caller", "auto reject" or some variation.
In addition, you can proactively register a phone number, whether for yourself or on someone else's behalf, using the FTC's Do Not Call Registry at https://www.donotcall.gov/. The site allows you to add up to three numbers at one time for an associated email address. It also provides the option to check if you've already registered a number.
iPhone instructions to block calls: https://support.apple.com/en-us/HT201229
Android instructions to block calls: http://www.wikihow.com/Block-a-Number-on-Android (varies by phone make)