Your cell phone doesn't have to be registered with Fidelity. If your present or former employer has it, then your 401k or pension fund admin, if Fidelity has it. You employer forwards all contact info to Fidelity.
6:52am PST they called - this phone call is way out of bounds. I did not answer and they can not legally call you unless it is between the hours of 8am and 8pm unless they have your verbal or written consent.
They said they were from Fidelity and wanted to talk to me about my 401k on a recorded line. the number called has been on the do not call list for years.