Ring Groups "Do not disturb"

Hello,

I’ve got a problem with ring groups. I create a test ring group e.g. 305 with 300 as extension, only one extension. If I call 305, I got a “do not disturb” answer for an unknown reason. Calling 300 directly is working. I also checked in the extensions settings module and the extension 300 does not have a specific setting (No DND ticked for example).

Any idea what can be checked? I also rebooted the server but still the same

Going to need a call trace to diagnose this.