this is actually true with cell providers, they can only provide the calls that are received or are placed by their customers
however, if u knew the number that placed the calls to ur cell phone, u would subpoena their records on the other end
this is why its important to take pictures of your caller id screen, its the only way to have a record of your missed calls
All cell providers keep records of line capture or line seizure events.
An event occurs when someone calls you or you call them.
There is no need for a call to be completed (answered) for an event to occur and be logged.
The log will show the calling or called party number, the route the call took through the network, and the destination number (which may or may not be your own cell number, depending on voicemail or forwarding), capture duration.
Regular customer service will not have access to these logs. These logs are what the cell company issues in response to a court order or subpoena - only their subpoena compliance department will release them.
Here is a list of subpoena compliance contact centers for the various carriers: http://www.tcpalaw.com/free/addr.htm