[SR-Users] issue with rewrite to domain in failure route

Hi I'm building some system with failover trunk but my providers requires to set their doamin in domain part of To Header so when I rewrite it at the my failure_route $td = FAILOVER_PROVIDER my To filed looks like To: <sip: 123(a)my.failover.providermy.main.provider&gt; what i tried: Move this change to BRANCH_ROUTE: here tried as $td = as uac_replace_to('',"newToFieldValue) Move to the my custom route with both variants But result is the same kamailio 5.1 version: kamailio 5.1.5 (x86_64/linux) d06080 flags: STATS: Off, USE_TCP, USE_TLS, USE_SCTP, TLS_HOOKS, USE_RAW_SOCKS, DISABLE_NAGLE, USE_MCAST, DNS_IP_HACK, SHM_MEM, SHM_MMAP, PKG_MALLOC, Q_MALLOC, F_MALLOC, TLSF_MALLOC, DBG_SR_MEMORY, USE_FUTEX, FAST_LOCK-ADAPTIVE_WAIT, USE_DNS_CACHE, USE_DNS_FAILOVER, USE_NAPTR, USE_DST_BLACKLIST, HAVE_RESOLV_RES ADAPTIVE_WAIT_LOOPS=1024, MAX_RECV_BUFFER_SIZE 262144 MAX_URI_SIZE 1024, BUF_SIZE 65535, DEFAULT PKG_SIZE 8MB poll method support: poll, epoll_lt, epoll_et, sigio_rt, select. id: d06080 compiled on 00:43:08 Aug 23 2018 with gcc 6.3.0