Manipulating Sip Headers

Hello i am getting sip traffic from a server but the SIP URI contains extra information. My asterisk is rejecting these sip invites. Can anyone please help me.

My current sip reqest is something like this:

INVITE sip:1234;phone-context=private@;user=phone SIP/2.0

Previously this request was as follows and my asterisk accepted invites with no issues:

INVITE sip:1234@

If someone can tell me how i can use those extra arguments to select that my sip user is “phone” and my context is “private” it will be beneficial for me. Thanks