VDB 2020 release and DC transformer?

Hello, I was hoping you could clarify something for me. On the product page for the video doorbell (2020 release) you say, under power and connectivity tech specs: “Can be hardwired to an existing doorbell system or transformer for continuous charging (8-24 VAC, 40VA max, 50/60Hz) No halogen or garden-lighting transformers; **no DC transformer/power supply**” But, you make a product called “Plug-In Adapter (2nd Generation)” which you say it works with “Video Doorbell - 2020 Release”, but under that products power and connectivity tech specs you say the power output is “24VDC, 0.5A, 12.0W” So my question is, if you can’t use a DC transformer for the ring video doorbell 2020 release, why do you sell a DC transformer for it?