diff --git a/cameleer3-server-app/src/main/java/com/cameleer3/server/app/search/OpenSearchLogIndex.java b/cameleer3-server-app/src/main/java/com/cameleer3/server/app/search/OpenSearchLogIndex.java
index a3a8de15..4bf970f9 100644
--- a/cameleer3-server-app/src/main/java/com/cameleer3/server/app/search/OpenSearchLogIndex.java
+++ b/cameleer3-server-app/src/main/java/com/cameleer3/server/app/search/OpenSearchLogIndex.java
@@ -110,7 +110,11 @@ public class OpenSearchLogIndex {
                 bool.must(Query.of(q -> q.term(t -> t.field("agentId").value(FieldValue.of(agentId)))));
             }
             if (exchangeId != null && !exchangeId.isEmpty()) {
-                bool.must(Query.of(q -> q.term(t -> t.field("exchangeId").value(FieldValue.of(exchangeId)))));
+                // Match on top-level field (new records) or MDC nested field (old records)
+                bool.must(Query.of(q -> q.bool(b -> b
+                        .should(Query.of(s -> s.term(t -> t.field("exchangeId").value(FieldValue.of(exchangeId)))))
+                        .should(Query.of(s -> s.term(t -> t.field("mdc.camel.exchangeId").value(FieldValue.of(exchangeId)))))
+                        .minimumShouldMatch("1"))));
             }
             if (level != null && !level.isEmpty()) {
                 bool.must(Query.of(q -> q.term(t -> t.field("level").value(FieldValue.of(level.toUpperCase())))));