Unable to Pair Schlage BE469ZP with Ring

I have been struggling with this for nearly a year. Here are what I have tried. 1. I tried connecting the lock with Ring using the default procedure in the app (tapping the BE469ZP option) but there was no "listening to device..." pop-out after I scanned the QR code. Instead, I got the attached screen with "Put the batteries in the lock". However, the batteries are already in the lock. 2. I tried connecting the lock manually (tapping the "ADD MANUALLY" option). It looked smooth at the beginning but I got a red light on the lock's Z-wave chip and "Device Security Error" in the Ring app. 3. I tried upgrading the Ring Alarm firmware and rebooting the Base station. The same results turned out in Step 1 or 2. 4. I tried factory resetting the lock. The same results turned out in Step 1 or 2. 5. I tried clearing the Z-wave chip on the lock following the steps in this thread: [https://community.ring.com/t5/Ring-Alarm/Schlage-Lock-not-connecting-with-Ring-Alarm-hub/m-p/1245](https://community.ring.com/t5/Ring-Alarm/Schlage-Lock-not-connecting-with-Ring-Alarm-hub/m-p/1245). The same results turned out in Step 1 or 2. BTW, after each time I failed to pair the lock with Ring, I remove the lock from the app. Any other suggestions?