Ring Intercom and Urmet 1122/31

Hi I'm trying to connect Ring Intercom with an Urmet 1122/31 kit . It's a 2 wire intercom. In the compatibility list, there is a 1122/1, but it has to connect to 5 wires and the codes, except for 1 and 2, are missing in my case. I tried to connect only A1 and A2 to 1 and 2, but when someone presses the outside button, nothing happen. Instead, if I pick up the internal phone, it's like someone presses the button Below, you can find a picture and the official connection schema. Can you please help to understand if it will ever work? Thanks  [Link to Urmet 1122/31manual](https://www.urmet.com/FileDownload.ashx?idDocumento=507956&estensioneFile=pdf&tipoDocumento=libretti&azienda=Urmet)