Driver's side door seems to take a while to sense me, but the rear door opens quickly all the time, any idea why?

[GodsPeace]

Hey everyone. It's not a big deal but it seems to take what feels like a long time for my door to unlock but whenever I use the door behind the driver's door it opens immediately. Could the phone's signal strength be an issue? Sometimes it seems like I need to turn on the phone's screen but that isn't the case when I open the rear door or trunk.