There have been many reporting of similar situations. These are considered by the masses to be a paranormal phenomenon called Phone Calls From The Dead (PCFTD). The first I heard about this was from Queen Of The Damned by Anne Rice. Jesse, a main character who is a red haired psychic archaeologist, decides to visit Lestat's old townhome in New Orleans. She tries to disprove the reality of the book, so she tears down wallpaper to look for evidence of the fire. She finds a secret door in deceased Claudia's room where many of her things were placed. Jesse loses track of time, reading Claudia's diary when the disconnected phone rings from the hall. Jesse scrambles, knocking the phone off the hook. A "tiny and thin, a woman's voice came out of it," saying, "Jesse?" Jesse quickly left. The voice on the other end belonged to Claudia. I decided to do more research on this phenomena, and I found that there are many documented occurrences. This happening is related to the EVP (electronic Voice Phenomenon). I've heard about short conversations to conversations lasting up to thirty minutes. The deceased caller may be bearing an urgent message or a simple greeting. One thing is the same- when the recipient mentions that the caller is dead, the call immediately terminates.
I myself have not had a phone call from beyond, but I still find it incredibly interesting. It must be such an eerie experience. Is this really paranormal? I've tried looking up explanations for PCFTD. If I were more of a scientist, I'm sure I would come up with something about theoretical physics and electromagnetism. Alas, I am not. Psychologists might say that it is a hallucination brought on by grief felt from the "caller's" death. It could even be someone butt dialing. Maybe even a prank call. If it is paranormal, then it is believed that spirits can manipulate technology. Perhaps we will never know, and maybe it is better that way.
Here are some YouTube videos of people who recorded this happening. I'm not sure how real these are or if they are credible at all. The connections are very bad, and it is difficult to hear the words being said.