Mxone 7.2 - outgoin call from ip phone gives arror " anonymous"

[abmitel]

Hi
Mxone 7.2 , issue in outgoing call from ip phone , it gives error "anonymous" on the ip phone display after i dial the number

but same time outgoing works fine from analog extension and digital extension

all incoming calls are ok

[bojo387]

What IP Phone? What do you see in a packet trace?