diff --git a/src/qiskit_qec/linear/symplectic.py b/src/qiskit_qec/linear/symplectic.py
index fdbb5d25..3b749163 100644
--- a/src/qiskit_qec/linear/symplectic.py
+++ b/src/qiskit_qec/linear/symplectic.py
@@ -690,7 +690,7 @@ def _build_hyper_partner(matrix, index: int) -> np.ndarray:
     for i in range(ncols):
         if heads[i] == 1:
             result[i] = trans_e_index[pivot]
-            pivot = +1
+            pivot += 1
 
     return result