Ok so I hope I explain this properly because I'm kind of freaked out by it. When a friend or anyone calls my phone and I answer the call all of a sudden a third party caller appears to be on the line listed as "Unknown". Once I end the call with my friend, the "Unknown" stays active unless I end that call as well. It doesnt happen with every caller but I've noticed it happening more frequently lately. Is someone tapping/listening in to my call or trying to GPS my location? I've been googling but I cant find any forum that mentions this. I've attached a photo with an example. Please help! 
