There was an informer

I recently obtained documents from the police that  an informer named Beemer/Beamer reported to them that he had been talking to me on a regular basis.  The only problem with this information is that I have never heard of a Beamer or Beemer and have never had regular phone calls with any stranger. I know all of the men in my friendship circle and have known them for a long time.  The state prosecutor told the judge that there was no informer.  These documents from the police indicate that there was an informer.