diff --git a/src/main/java/com/powsybl/openloadflow/knitro/solver/NonLinearExternalSolverUtils.java b/src/main/java/com/powsybl/openloadflow/knitro/solver/NonLinearExternalSolverUtils.java
index 868996c..dcf8392 100644
--- a/src/main/java/com/powsybl/openloadflow/knitro/solver/NonLinearExternalSolverUtils.java
+++ b/src/main/java/com/powsybl/openloadflow/knitro/solver/NonLinearExternalSolverUtils.java
@@ -43,7 +43,7 @@ public static boolean isLinear(AcEquationType typeEq, List<EquationTerm<AcVariab
     }
 
     // Return lists of variables and coefficients to pass to Knitro for a linear constraint
-    public VarAndCoefList getLinearConstraint(AcEquationType typeEq, int equationId, List<EquationTerm<AcVariableType, AcEquationType>> terms) throws UnsupportedOperationException {
+    public VarAndCoefList getLinearConstraint(AcEquationType typeEq, List<EquationTerm<AcVariableType, AcEquationType>> terms) throws UnsupportedOperationException {
         VarAndCoefList varAndCoefList = null;
 
         // Check if the constraint is linear