I came on the web cite this evening with the same dilemma. I have had two solar chargers now from ring and neither of them work. When the little automated chat screen popped up I asked questions about it and never got the correct answer. I finally did get an answer and was told that the solar charger is not compatible with the ring capital r doorbells. I will be contacting the company for a shipping label and a full refund the cost of the charger and the sales tax.
I hope this helps!