Extension communication problems using Cisco 7940 phones

I bought some Ciscos IP phones. I have changed the configuration to SIP and did all configuration process but:
What I can do:
Call to the outside
Call to internal soft phones
I cannot:
receive calls in the 7940 Cisco phones
call internal extensions using the 7940 phones to other 7940 phones.
receive calls from internal soft-phones to 7940 extensions

In my free PBX I have the following configuration:

secret :xxxx
dtmfmode: rfc2833
context: from-internal
type: friend
nat: no
port 5060
qualify: yes
dial: SIP/201
mailbox: 201@device

I appreciate your help.
Best regards

try nat=never

it did not work with “never” or “0”

Thanks for your help

What version SIP software? How is your xml formating?

I should have been more specific. NAT=never and Qualify=Yes must be set in the FreePBX extension.

the SW in the phone is the P0S3-8-12-00. the FreePBX software is version is 2.3.1
best regards

I’m not exactly sure why, but I never achieved to have the host line working.

Then clear the host line and replace by host= dynamic

And in deny put
permit put your

but during the test phase, you can even remove the two deny/permit lines as that’s more for a safety aspects.

I have seen this when the xml formatting is not quite right in the SEPmacaddress file.