On update 15.2 and Find my iPhone locations for my family now work very poorly. Most of the time their last location is 12-24 hours old. This was not a problem before the update. We all have 12 or 13 Pro's if that matters.
I am sorry to hear that you are experiencing issues with the Find My iPhone location detection. Let's see how we can help resolve this. When did you receive the most recent update? Is location working for other apps such as Maps?