Are you trying to change the settings on the phone itself? Try going through your MyVerizon account online to be sure teh Caller ID feature is enabled.
Log in at verizonwireless.com, on the left side under Manage My Account, choose Change Features. Choose which phone line (if applicable), and then scroll down to the Caller ID section, about halfway down the page under "Additional Features". Be sure CallerID Blocking is NOT added.
Hope this helps.