diff --git a/cpp/src/branch_and_bound/symmetry.hpp b/cpp/src/branch_and_bound/symmetry.hpp
index f8e9ce469b..64ecbd6fd6 100644
--- a/cpp/src/branch_and_bound/symmetry.hpp
+++ b/cpp/src/branch_and_bound/symmetry.hpp
@@ -319,7 +319,7 @@ class orbital_fixing_t {
       node = node->parent;
     }
 
-    surviving_generators_.resize(max_generators_);
+    surviving_generators_.resize(symmetry->num_generators);
     std::iota(surviving_generators_.begin(), surviving_generators_.end(), 0);
 
     // Seed cumulative fixings from the parent's stored orbital fixings.