Ring keypad battery not charging

2hrs on phone and 2 replaced keypads I learned I would have to purchase a new one at $50ish dollars plus shipping.Keypad would not charge. I had tried every single possibility! The reason as I was told was because both were under a year but the replacement was not covered. I ask myself are the replacements defective? used? or seconds? , I don`t get it! I finally got so frustrated I canceled my subscription. What I feel most upset about is our son, a Digital forensic police detective of 25+ yrs. ,gave it to us for a gift because he wanted me (severely hearing impaired) to be safe. Why arn`t replacements worth the warranty??? . Thankyou