Having read this topic:
https://community.reolink.com/topic/6400/video-doorbell-person-detection-is-busted
... I encountered the same problem with the same firmware and hw versions. I'm using the Wifi version on a 5Ghz network.

I bit the bullet and requested support with the help of the online form (incl. pictures as requested) on Saturday, a bit later in the midday. Lo and behold within 10 minutes I got a reply, not a canned response, nope: the team at the other end of the line picked up my issue with the doorbell and started to assist me throughout the next couple of days. Amazing.

Here's my experience:
In my situation there's a 3-4 meter path leading straight to the front door. Streetlights at the left and at the opposite side of my street is another street coming almost towards me, to the right of it is a 24h gas station with their own lights and people with their cars coming in and going away day and night. Not an easy setup for a doorbell like this.

The doorbells Visitor setting was working like expected, no problems there.

The problems were with the Person detection, lots of them. Now I had set a Detection mask and the way I set it up seemed to be the culprit. It was too much. Now what I didn't realise is when a person gets on your path on their way to your front door, that person with the detection mask I previously set was only detected when completely within the cameras view. It started with only the legs of the person coming in view, after a while when the person gets nearer more of the persons body comes in view and thus into the game. And then somewhere (see sensitivity settings) the detection starts, and that was too late. So I readjusted the Detection Mask step by step to make it less masking the picture. Now, when a person is entering the path to my front door, at that same moment the complete body of that person is in view and not just the shoes and/or legs. That made a huge difference. However, it's still not perfect and that could probably have to do with two other things: the notifications coming way to slow, and when people at the aforementioned gas station are leaving in the dark hours with their cars and lights on, the detection gets triggered. So I readjusted the Detection Mask another time to mask that out and it's almost working at an acceptable level. However I still get a couple of false alerts now and then.

My suggestions for the team at Reolink:
1. make the push notifications selectable at consumers will to "on the device", that is without being forced to first send detection notifications to Reolink servers and from there back to the phone connected to the same network the doorbell is on (with Google/Apple server in between), but instead straight to the device (i.e. phone) to receive the notification way faster. The slowness of the notifications comes from the Reolink servers in between if you ask me. 
2. Offer an on/off toggle in the software for an overlay working at dark times only (something like Detection Mask) for filtering car lights, to prevent those from triggering the Detection.

I would be happy to help and test these things.

FWIW: I could say that I'm not that satisfied completely with this doorbell, however I also realise it's a consumer's grade doorbell/camera and not a full professional piece of equipment for the money paid. At the same time there's also the support team which acted fast, to the point and assisted me, even during weekend. What I would like to see is Reolink adding these features I mentioned above so their doorbell and possibly other cams in the portfolio are blowing all others out of the water. Maybe a dream never coming true, however I somehow feel the potential is right there.