diff --git a/tests/lbm/codegen/FluctuatingMRT.cpp b/tests/lbm/codegen/FluctuatingMRT.cpp
index 9fccc77afe69cd200a65e2ead4fefb4c72a7f5bc..f7657d25953b6a18f334e49b7d9f7137cd9e566f 100644
--- a/tests/lbm/codegen/FluctuatingMRT.cpp
+++ b/tests/lbm/codegen/FluctuatingMRT.cpp
@@ -74,8 +74,9 @@ int main( int argc, char ** argv )
    BlockDataID pdfFieldId = lbm::addPdfFieldToStorage( blocks, "pdf field", latticeModel, initialVelocity, real_t(1) );
    BlockDataID flagFieldId = field::addFlagFieldToStorage< FlagField_T >( blocks, "flag field" );
 
-   // create and initialize boundary handling
+   // create and initialize flag field
    const FlagUID fluidFlagUID( "Fluid" );
+   geometry::setNonBoundaryCellsToDomain<FlagField_T>(*blocks, flagFieldId, fluidFlagUID);
 
    // create time loop
    SweepTimeloop timeloop( blocks->getBlockStorage(), timesteps );
@@ -86,7 +87,12 @@ int main( int argc, char ** argv )
 
    // set the RNG counter to match the time step and propagate it to the fields' copies of the lattice model
    timeloop.add() << BeforeFunction( [&](){ latticeModel.time_step_ = uint32_c(timeloop.getCurrentTimeStep()); }, "set RNG counter" )
-                  << Sweep( [&]( IBlock * block ){ block->getData< PdfField_T >( pdfFieldId )->resetLatticeModel( latticeModel ); }, "set RNG counter" );
+                  << Sweep( [&]( IBlock * block ){
+                        auto field = block->getData< PdfField_T >( pdfFieldId );
+                        field->resetLatticeModel( latticeModel );
+                        field->latticeModel().configure( *block, *blocks );
+                        WALBERLA_ASSERT_EQUAL( field->latticeModel().time_step_, latticeModel.time_step_ );
+                     }, "set RNG counter" );
    // add LBM sweep and communication to time loop
    timeloop.add() << BeforeFunction( communication, "communication" )
                   << Sweep( LatticeModel_T::Sweep( pdfFieldId ), "LB stream & collide" );