&&linphone_address_get_transport(contact_addr)!=LinphoneTransportUdp/*with udp, there is a risk of port reuse, so I prefer to not do anything for now*/){
/*need to save current contact in order to reset is later*/
&&linphone_address_get_transport(contact_addr)!=LinphoneTransportUdp/*with udp, there is a risk of port reuse, so I prefer to not do anything for now*/