diff --git a/apps/emqx_authz/src/emqx_authz_api_sources.erl b/apps/emqx_authz/src/emqx_authz_api_sources.erl
index 73f28176b..731c5d40f 100644
--- a/apps/emqx_authz/src/emqx_authz_api_sources.erl
+++ b/apps/emqx_authz/src/emqx_authz_api_sources.erl
@@ -232,10 +232,7 @@ source(get, #{bindings := #{type := Type}}) ->
                 #{annotations := #{id := ResourceId }} ->
                     case lookup_from_all_nodes(ResourceId) of
                         {ok, StatusAndMetrics} ->
-                            Fun = fun ({Key, Val}, Map) -> maps:put(Key, Val, Map) end,
-                            {200, lists:foldl(Fun,
-                                              read_certs(Source),
-                                              maps:to_list(StatusAndMetrics))};
+                            {200, maps:merge(read_certs(Source), StatusAndMetrics)};
                         {error, ErrorMsg} -> {500, ErrorMsg}
                     end;
                 _ -> {200, read_certs(Source)}