[SR-Users] Remove a Line from SDP

Hi all, I am trying to remove a line from the SDP body of INVITE on kamailio 4.4 via SDPOPS module but it does not work even though there is no any error message. This is how I configure kamailio.cfg, it matches with if condition and executes "sdp_remove_line_by_prefix" function, but when I check sended INVITE, I still see the line that beginning with "a=rtpmap". I thought, in the RELAY function, the sdp body might not prepared yet? Is there any suggestion to remove a line from the SDP body? route[RELAY] { ... ... if(is_method("INVITE")) { if( $ct =~ "0553847<tel:+10553847>aaaa"){ xlog("L_WARN", "$ct check_this \n"); sdp_remove_line_by_prefix("a=rtpmap"); } } } /path/kamailio[10332]: exec: *** cfgtrace:request_route=[RELAY] c=[/path/kamailio.cfg] l=614 a=16 n=if /path/kamailio[10332]: exec: *** cfgtrace:request_route=[RELAY] c=[/path/kamailio.cfg] l=611 a=26 n=xlog /path/kamailio[10332]: WARNING: <script>: <sip:0553847<tel:+10553847>aaaa@x.x.x.x:5060> check_this /path/kamailio[10332]: exec: *** cfgtrace:request_route=[RELAY] c=[/path/kamailio.cfg] l=612 a=25 n=sdp_remove_line_by_prefix /path/kamailio[10332]: exec: *** cfgtrace:request_route=[RELAY] c=[/path/kamailio.cfg] l=622 a=16 n=if Regards Egemen U. Get Outlook for Android<https://aka.ms/ghei36>