Checking extension 6104 …
# asterisk -x " pjsip show endpoint 6104" | grep suppress
suppress_q850_reason_headers : false
Edit the file:
/etc/asterisk/pjsip.endpoint_custom_post.conf
then add the following lines:
[6104](+type=endpoint)
suppress_q850_reason_headers = yes
Save the file, reload the dialplan and checking again:
# asterisk -x " pjsip show endpoint 6104" | grep suppress
suppress_q850_reason_headers : true