That sounds like a provider issue. Are you doing testing with the provider?
Any alarms on the DS1? If so, the D & B's won't come alive! No DS1 alarms, then the switch may have the channels busied out. Contact your service provider or open a trouble ticket with repair service. The B & D channels are assigned to trunk groups in the CO switch similar to DID trunks. So they can be busied out! One point of info: no D channel, then no B channels. The DCH is the communications path between the CO switch and the Legend/Magix equipment. Without it nothing will happen!
You may need to verify translations with the switch person for the SDN in relation to the PRI info for the Magix.
Hope this helps!
....JIM....