I want to change P-Assertion Identity in trunk setting from <sip:09234xxxxxx> to <tel:09234xxxxxx>
because Sip provider they allow only P-Assertion Identity<tel:09234xxxxxx> in package.
I did not find any parameter to change.
Please note that this is not possible as the outbound parameters are set in the SIP engine of the system. I would recommend posting this as a feature request to our ideas section of the forum https://www.3cx.com/community/forums/3cx-ideas/ . All posts are reviewed by their corresponding Departments and, if feasible and voted for by other users as well, may be implemented in an upcoming service pack or update.