Asterisk on Azure cannt not answer call

[jsonchan000]

I installed asterisk on Azure ubuntu. And I using linphone as a endpoint. The endpoint was connected (can see Not in use in ‘pjsip show endpoints’).

However, when I call 100 (hello world), the endpoint keep showing: ‘outgoing call’ (which mean the call is not yet answer), and asterisk do not display any warning and error.

Here is my code:

pjsip.conf

[transport-udp]
type=transport
protocol=udp
bind=0.0.0.0:5060

local_net=XX.XX.XX.XX/20                      ;local ip addr
external_media_address=XX.XX.XX.XX        ;public ip addr
external_signaling_address=XX.XX.XX.XX   ;public ip addr

[1001]
type=endpoint
context=from-internal
transport=transport-udp
disallow=all
allow=ulaw,alaw
media_encryption=sdes
auth=1001
aors=1001

[1001]
type=auth
auth_type=userpass
password=XXXXXXXXXXXXX
username=1001

[1001]
type=aor
max_contacts=1

extensions.conf

[from-internal]
exten => 100,1,Answer()
same => n,Wait(1)
same => n,Playback(hello-world)
same => n,Hangup()

Azure network rules:

Inbound: 
5060-5061 (any protocol)
10000-20000 (any protocol)

Outbound:
5060-5061 (any protocol)
10000-20000 (any protocol)

Thanks