I finally got the answer from Reolink support.

The Reolink NVR is NOT COMPATIBLE with ALL Reolink NVRs, despite what they claim on their website.

The Doorbell can work as camera and record the video on ALL Reolink NVRs, but the Doorbell functionalities are limited to the newest Reolink NVRs.

I have RLN8-410-E H3MB16 and the Doorbell is only compatible with H3MB18/N2MB01/N3MB01/N5MB01/N6MB01/N7MB01.

Support told me that to make it work I need an additional POE switch/injector. But it is not fair. This was never highlighted anywhere and it is adding additional costs.

Reolink, sorry, but you really messed up this time, and I'm not happy about this.

@pleijers_588217073831983
I have the same issue. Doorbell is recognized just as a camera. If I try to manually add it by scanning the QR code on the back, I get a "connection failed" error message.
NVR firmware is updated to latest version. I also reset it to default settings and also reset the doorbell many times, but it gets added automatically as camera to the NVR and each attempt to manually add it as doorbell is failing.

I finally got the answer from Reolink support.

The Reolink NVR is NOT COMPATIBLE with ALL Reolink NVRs, despite what they claim on their website.

The Doorbell can work as camera and record the video on ALL Reolink NVRs, but the Doorbell functionalities are limited to the newest Reolink NVRs.

I have RLN8-410-E H3MB16 and the Doorbell is only compatible with H3MB18/N2MB01/N3MB01/N5MB01/N6MB01/N7MB01.

Support told me that to make it work I need an additional POE switch/injector. But it is not fair. This was never highlighted anywhere and it is adding additional costs.

Reolink, sorry, but you really messed up this time, and I'm not happy about this.

@pleijers_588217073831983
I have the same issue. Doorbell is recognized just as a camera. If I try to manually add it by scanning the QR code on the back, I get a "connection failed" error message.
NVR firmware is updated to latest version. I also reset it to default settings and also reset the doorbell many times, but it gets added automatically as camera to the NVR and each attempt to manually add it as doorbell is failing.

@reolink-fiona

I'd really like to have following features:

Power: POE from Reolink NVR
Video Resolution: at least Full HD
Audio: Two-way audio (with noise cancellation)
Detection: Motion detection (+ AI detection)
Storage: Reolink NVR
Support third-party software like HomeAssistant

Thank you!