I installed the Ring Intercom by integrating it with my existing Fermax apartment handset so I could remotely unlock the building entrance door via the Ring app. Whenever a visitor dials my apartment on the building intercom, the Ring device detects the signal from the handset circuitry and sends a notification to my app, allowing me to speak and buzz them in. This setup worked seamlessly for 8 months. However, about 3 weeks ago, it stopped functioning completely. I no longer receive any notifications or calls in the Ring app when someone buzzes my apartment, although the physical Fermax handset inside my home still rings and functions normally. I have already completed extensive troubleshooting with a Ring support agent—including pulling the battery, disconnecting and reconnecting the terminal wiring on the circuit board, and reinstalling the Ring app. I also checked with our building intercom technicians, who confirmed that no modifications or system changes have been made to the central building setup.

can someone please suggest me what is wrong here , has anyone ever had somethign like this happened?

also can someone pelase suggest me an alternate device outside of ring ?