Hear no busy tone through PRI

When I call a extension from PSTN through a PRI E1 trunk
who is busy,
has no Voice Mailbox and
Call Waiting is disabled ->

I should get a busy tone on the phone.

But I hear nothing until hang up.

When I look at asterisk I see the following:
.


– Executing [[email protected]:4] NoOp(“Zap/2-1”, “Returned from dialparties with no extensions to call and DIALSTATUS: BUSY”) in new stack
– Executing [[email protected]:10] GotoIf(“Zap/2-1”, “0?exit|return”) in new stack
– Executing [[email protected]:11] Set(“Zap/2-1”, “SV_DIALSTATUS=BUSY”) in new stack
– Executing [[email protected]:12] GosubIf(“Zap/2-1”, “0?docfu|1”) in new stack
– Executing [[email protected]:13] GosubIf(“Zap/2-1”, “0?docfb|1”) in new stack
– Executing [[email protected]:14] Set(“Zap/2-1”, “DIALSTATUS=BUSY”) in new stack
– Executing [[email protected]:15] NoOp(“Zap/2-1”, “Voicemail is novm”) in new stack
– Executing [[email protected]:16] GotoIf(“Zap/2-1”, “1?s-BUSY|1”) in new stack
– Goto (macro-exten-vm,s-BUSY,1)
– Executing [[email protected]:1] NoOp(“Zap/2-1”, “Extension is reporting BUSY and not passing to Voicemail”) in new stack
– Executing [[email protected]:2] GotoIf(“Zap/2-1”, “0?exit|1”) in new stack
– Executing [[email protected]:3] PlayTones(“Zap/2-1”, “busy”) in new stack
– Executing [[email protected]:4] Busy(“Zap/2-1”, “20”) in new stack

There is a PlayTones(“Zap/2-1”, “busy”) in new stack
but I hear nothing.

any tipps?