diff --git a/src/net/matching.c b/src/net/matching.c
index 8ef35f5da..56603fe0a 100644
--- a/src/net/matching.c
+++ b/src/net/matching.c
@@ -80,10 +80,12 @@ _z_matching_listener_t _z_matching_listener_declare(_z_session_rc_t *zn, const _
 
 z_result_t _z_matching_listener_entity_undeclare(_z_session_t *zn, _z_zint_t entity_id) {
     _z_matching_listener_intmap_iterator_t iter = _z_matching_listener_intmap_iterator_make(&zn->_matching_listeners);
-    while (_z_matching_listener_intmap_iterator_next(&iter)) {
+    bool has_next = _z_matching_listener_intmap_iterator_next(&iter);
+    while (has_next) {
         size_t key = _z_matching_listener_intmap_iterator_key(&iter);
         _z_matching_listener_state_t *listener = _z_matching_listener_intmap_iterator_value(&iter);
         _Z_DEBUG("_z_matching_listener_entity_undeclare: listener=%p", (void *)listener);
+        has_next = _z_matching_listener_intmap_iterator_next(&iter);
         if (listener->entity_id == entity_id) {
             _Z_DEBUG("_z_matching_listener_entity_undeclare: entity=%i, listener=%i", (int)entity_id, (int)key);
             _z_remove_interest(zn, listener->interest_id);
diff --git a/tests/z_api_matching_test.c b/tests/z_api_matching_test.c
index 8c09ad7ed..0a9c621c7 100644
--- a/tests/z_api_matching_test.c
+++ b/tests/z_api_matching_test.c
@@ -128,7 +128,6 @@ void test_matching_sub(bool background) {
 
     z_owned_publisher_t pub;
     assert_ok(z_declare_publisher(z_session_loan(&s1), &pub, z_view_keyexpr_loan(&k_pub), NULL));
-    z_sleep_s(10);
 
     z_owned_closure_matching_status_t closure;
     z_closure_matching_status(&closure, on_receive, on_drop, (void*)(&context));
diff --git a/tests/z_collections_test.c b/tests/z_collections_test.c
index 69183050b..c49121569 100644
--- a/tests/z_collections_test.c
+++ b/tests/z_collections_test.c
@@ -361,12 +361,13 @@ void int_map_iterator_deletion_test(void) {
     _z_str_intmap_insert(&map, 40, _z_str_clone("D"));
 
     _z_str_intmap_iterator_t iter = _z_str_intmap_iterator_make(&map);
+    _z_str_intmap_iterator_next(&iter);
     for (size_t s = 4; s != 0; s--) {
         assert(s == _z_str_intmap_len(&map));
-        _z_str_intmap_iterator_next(&iter);
         size_t key = _z_str_intmap_iterator_key(&iter);
         assert(strlen(_z_str_intmap_iterator_value(&iter)) == 1);
         _z_str_intmap_remove(&map, key);
+        _z_str_intmap_iterator_next(&iter);
     }
     _z_str_intmap_clear(&map);
 }