diff --git a/contribs/drt-extensions/src/main/java/org/matsim/contrib/drt/extension/preplanned/optimizer/PreplannedDrtOptimizer.java b/contribs/drt-extensions/src/main/java/org/matsim/contrib/drt/extension/preplanned/optimizer/PreplannedDrtOptimizer.java
index fd0f6672826..5e47c385106 100644
--- a/contribs/drt-extensions/src/main/java/org/matsim/contrib/drt/extension/preplanned/optimizer/PreplannedDrtOptimizer.java
+++ b/contribs/drt-extensions/src/main/java/org/matsim/contrib/drt/extension/preplanned/optimizer/PreplannedDrtOptimizer.java
@@ -77,7 +77,7 @@ public PreplannedDrtOptimizer(DrtConfigGroup drtCfg, PreplannedSchedules preplan
 			TravelTime travelTime, TravelDisutility travelDisutility, MobsimTimer timer, DrtTaskFactory taskFactory,
 			EventsManager eventsManager, Fleet fleet, ScheduleTimingUpdater scheduleTimingUpdater) {
 		Preconditions.checkArgument(
-				fleet.getVehicles().keySet().equals(preplannedSchedules.vehicleToPreplannedStops.keySet()),
+				fleet.getVehicles().keySet().containsAll(preplannedSchedules.vehicleToPreplannedStops.keySet()),
 				"Some schedules are preplanned for vehicles outside the fleet");
 
 		this.mode = drtCfg.getMode();
diff --git a/contribs/dvrp/src/main/java/org/matsim/contrib/zone/skims/DvrpTravelTimeMatrixParams.java b/contribs/dvrp/src/main/java/org/matsim/contrib/zone/skims/DvrpTravelTimeMatrixParams.java
index a12930c5d42..52c3c332f09 100644
--- a/contribs/dvrp/src/main/java/org/matsim/contrib/zone/skims/DvrpTravelTimeMatrixParams.java
+++ b/contribs/dvrp/src/main/java/org/matsim/contrib/zone/skims/DvrpTravelTimeMatrixParams.java
@@ -20,6 +20,7 @@
 
 package org.matsim.contrib.zone.skims;
 
+import jakarta.validation.constraints.NotNull;
 import jakarta.validation.constraints.PositiveOrZero;
 import org.matsim.contrib.common.util.ReflectiveConfigGroupWithConfigurableParameterSets;
 import org.matsim.contrib.common.zones.ZoneSystemParams;
@@ -55,6 +56,7 @@ public class DvrpTravelTimeMatrixParams extends ReflectiveConfigGroupWithConfigu
 			+ " The unit is seconds. Default value is 0 s (for backward compatibility).")
 	@PositiveOrZero
 	public double maxNeighborTravelTime = 0; //[s]
+	@NotNull
 	private ZoneSystemParams zoneSystemParams;
 
 
@@ -101,6 +103,11 @@ public void handleAddUnknownParam(String paramName, String value) {
 	}
 
 	public ZoneSystemParams getZoneSystemParams() {
+		if(this.zoneSystemParams == null) {
+			SquareGridZoneSystemParams squareGridZoneSystemParams = new SquareGridZoneSystemParams();
+			squareGridZoneSystemParams.cellSize = 200;
+			this.zoneSystemParams = squareGridZoneSystemParams;
+		}
 		return zoneSystemParams;
 	}
 }