As a former cop I can also tell you that you can receive e-mails that look like they have the right e-mail address, except it might be "UPS.com" instead of "United Parcel Service.com" - just a made up example. The one that comes all the time has a title of UPS Package notification - same from post office. Unless you are expecting tracking info, don't open.
Also, it sounds basic, but ANY call you get from a company that asks ANY personal info, confirm a cell phone # etc. hang up! All companies do important correspondence these days via mail and/or in person. You would be surprised what slips through.