For a number of years, I had two (2) Ring Wire Doorbell Plus connected to my physical wall mounted chime box without any issues. One designated as front door bell and other  as designated as rear doorbell. One Pro Power Kit was attached to the in home chime box labels front and transformer. The other Pro Power Kit was attached to the in home chime box labels rear and transformer. Last year I purchased a Ring Wired Doorbell 4K Pro with Chime Mini Kit and still haven’t been able to get it working.

I replaced/upgraded the doorbell transformer with 24V 40VA Doorbell Transformer - Heavy-Duty Copper Core for Ring Pro/2. Removed Ring Wire Doorbell Plus from front door and replaced with Ring Wired Doorbell 4K Pro. Removed the Pro Power Kit from the in home chime box. Attached one wire from the Chime Mini Kit directly to the wire returning to the Ring Wired Doorbell 4K Pro (front door). (Bypassed the in home chime box). The other Chime Mini Kit wire connected to the in home chime box transformer screw, which is also used for the rear doorbell.

Rear doorbell still worked without any issues. Took many attempts to connect the front doorbell using Ring app. New doorbell (front) worked for several days then failed. Unable to either reconnect or indicates no power (light on the front would never illuminate). Using reset did not make a difference.

Contacted Ring support and eventually they said the “new” Doorbell 4K Pro was defective. Sent me a new one. After 6 months of repeated calls to Ring support and multiple attempts, customer support says this one is defective also. Another replacement arrived the other day.

I have requested a wiring diagram repeatedly to make sure I’m not hooking the two different doorbells up incorrectly. They either can’t understand what I want to do, or they tell me they don’t have any instructions. Using Google AI isn’t very clear with wiring.