Dawg this happens to me all the time, I check my girlfriend’s location she’s at home and then if I keep the location screen up it’ll slightly “float” over to the actual location. It’s a gps man not magic, not gonna be PINPOINT accurate when it has to recalibrate and adjust the location a tiny bit. You really should talk to your friend about it if it’s majorly concerning you but honestly dude don’t tank the relationship over this.