C7100V

I bought the NETGEAR Nighthawk AC1900 WiFi Cable Modem Router with Voice (C7100V). Id didnt come with a Battery, and contacted Netgear customer sevice. The representative told me that they didnt cary this battery and I should get one on Amazon. I asked him for the model number of the battery, but he didnt know it. I checked with Amazon, but the battery Amazon sells doest work, apparently it dosnt make ecectrical contact when inserted into the C7100V battery compatment and the customers thought the battery was bad. I called Netgear back and asked a different representative to get the model number from Nergear engineering since they designed the battery compartment and therefore must know the model of the battery. This second representative didnt get back to me. I emaild Nergear customer service to get information about his battery. No one replied.