Not Charging

Charging Problem Update: I installed a Ring2 on an existing electro-mechanical doorbell system with a 16 vac transformer. It worked great for over 5 weeks, charge level staying between 98% and 100%. Now the charge goes down 5% per day requiring me to remove the battery pack to charge it. The battery is not being charged internally. Voltage at the transformer is 17.1 volts. Voltage at the Ring2 rear terminals is 17.1 vac. Lack of a voltage drop at the ring terminals means that there is no charge current flowing into the Ring2. The Ring2 is not charging even though there is 17.1 vac at the terminals. I think there must be an internal failure of the charging circuit. I called the Ring help line (800-656-1918 ). They replaced the Ring2. This did not correct the problem. I even replaced my 16 volt transformer with a 24 volt transformer. I tested voltage and current at the Ring2 terminals. Voltage is at 24 vac, Current flow at the Ring2 terminals is 9 mA. There are many similar problems posted here on the Forum, A similar post here on the Forum stated that his charging problem occurred after a firmware upgrade. His issue was not temperature related as he lived in Southern Florida. As mine worked great for the first 5 weeks, And now I have the same problem, even with the new Ring2, and nothing in the enviornment is any different than the first 5 week, I am wondering if this is a firmware problem. My question to Ring technicians: Do you have a firmware issue causing this problem?