Motion Detector will not reconnect

Battery died on the Ring motion detector and I replaced it w/ the same CR123A model. As I'm setting up the device to add back to my Ring Alarm System, it does NOT recognize the device at all. I've followed the troubleshooting tips 50x now and nothting happens when I try to add the device. Can anyone offer a few words of advice? I'm literally sittign at the Base Station w/ my phone (which has the Ring app) and it simply won't add back. Please advise. Thanks,