diff --git a/fx.collections/hashtable.c b/fx.collections/hashtable.c
index 8ce5798..54c556e 100644
--- a/fx.collections/hashtable.c
+++ b/fx.collections/hashtable.c
@@ -114,6 +114,15 @@ static fx_status allocate_index_for_key(
 			break;
 		}
 
+		const struct fx_hashtable_item_p *item = fx_object_get_private(
+			table[index].i_item,
+			FX_TYPE_HASHTABLE_ITEM);
+		int cmp = fx_value_compare(&item->i_key, v);
+		if (cmp == 0) {
+			ok = true;
+			break;
+		}
+
 		index = (index + (i * i)) % table_size;
 		i++;
 	}
@@ -277,7 +286,6 @@ static fx_status hashtable_put(
 	fx_value_copy(&item_p->i_key, key);
 	fx_value_copy(&item_p->i_value, value);
 
-	assert(hashtable->t_items[index].i_item == NULL);
 	hashtable->t_items[index].i_item = item;
 	hashtable->t_count++;
 	return FX_SUCCESS;