diff --git a/src/Hipace.cpp b/src/Hipace.cpp
index dfe7c398fd..28eadafaca 100644
--- a/src/Hipace.cpp
+++ b/src/Hipace.cpp
@@ -744,7 +744,6 @@ void
 Hipace::WriteDiagnostics (int output_step, bool force_output)
 {
     HIPACE_PROFILE("Hipace::WriteDiagnostics()");
-    constexpr int lev = 0;
 
     // Dump before first and after last step, and every m_output_period steps in-between
     if (m_output_period < 0 ||
@@ -763,6 +762,7 @@ Hipace::WriteDiagnostics (int output_step, bool force_output)
     amrex::Vector<std::string> rfs;
 
 #ifdef HIPACE_USE_OPENPMD
+    constexpr int lev = 0;
     m_openpmd_writer.WriteDiagnostics(m_fields.getDiagF(), m_multi_beam, m_fields.getDiagGeom(),
                                       m_physical_time, output_step,  lev, m_fields.getDiagSliceDir(), varnames);
 #else