--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -15665,7 +15665,10 @@
 			frommismatch = !!strcmp(fromtag, sip_pvt_ptr->theirtag);
 			tomismatch = !!strcmp(totag, sip_pvt_ptr->tag);
 
-			if (frommismatch || tomismatch) {
+                        /* Don't check from if the dialog is not established, due to multi forking the from
+                         * can change when the call is not answered yet.
+                         */
+			if ((frommismatch && ast_test_flag(&sip_pvt_ptr->flags[1], SIP_PAGE2_DIALOG_ESTABLISHED)) || tomismatch) {
 				sip_pvt_unlock(sip_pvt_ptr);
 				if (frommismatch) {
 					ast_debug(4, "Matched %s call for callid=%s - pedantic from tag check fails; their tag is %s our tag is %s\n",