diff --git a/src/main/java/org/gcube/accounting/aggregation/scheduler/AggregationScheduler.java b/src/main/java/org/gcube/accounting/aggregation/scheduler/AggregationScheduler.java
index 73157ba..b31c6dc 100644
--- a/src/main/java/org/gcube/accounting/aggregation/scheduler/AggregationScheduler.java
+++ b/src/main/java/org/gcube/accounting/aggregation/scheduler/AggregationScheduler.java
@@ -26,10 +26,11 @@ public abstract class AggregationScheduler {
 	
 	protected static AggregationScheduler aggregationScheduler;
 	
+	static {
+		aggregationScheduler = new BufferAggregationScheduler();
+	}
+	
 	public static AggregationScheduler getInstance(){
-		if(aggregationScheduler==null){
-			aggregationScheduler = new BufferAggregationScheduler();
-		}
 		return aggregationScheduler;
 	}
 	
diff --git a/src/main/java/org/gcube/accounting/datamodel/BasicUsageRecord.java b/src/main/java/org/gcube/accounting/datamodel/BasicUsageRecord.java
index ad7c666..3f50abe 100644
--- a/src/main/java/org/gcube/accounting/datamodel/BasicUsageRecord.java
+++ b/src/main/java/org/gcube/accounting/datamodel/BasicUsageRecord.java
@@ -483,7 +483,7 @@ public abstract class BasicUsageRecord implements UsageRecord, Serializable {
 		}
 		
 		String classCanonicalName = utilityClass.getCanonicalName();
-		classCanonicalName.replace(utilityClass.getSimpleName(), usageRecordName);
+		classCanonicalName = classCanonicalName.replace(utilityClass.getSimpleName(), usageRecordName);
 		
 		try {
 			clz = (Class<? extends UsageRecord>) Class.forName(classCanonicalName);
diff --git a/src/main/java/org/gcube/accounting/datamodel/RawUsageRecord.java b/src/main/java/org/gcube/accounting/datamodel/RawUsageRecord.java
index 675f3ad..f68787b 100644
--- a/src/main/java/org/gcube/accounting/datamodel/RawUsageRecord.java
+++ b/src/main/java/org/gcube/accounting/datamodel/RawUsageRecord.java
@@ -198,7 +198,7 @@ public class RawUsageRecord extends BasicUsageRecord implements SingleUsageRecor
 	@Deprecated
 	public void setConsumerId(String consumerId) {
 		try{
-			setConsumerId(consumerId);
+			super.setConsumerId(consumerId);
 		} catch(Exception e){
 			logger.error("Unable to Set {}", CONSUMER_ID);
 		}
diff --git a/src/main/java/org/gcube/accounting/datamodel/basetypes/JobUsageRecord.java b/src/main/java/org/gcube/accounting/datamodel/basetypes/JobUsageRecord.java
index 6dad9d8..d87a795 100644
--- a/src/main/java/org/gcube/accounting/datamodel/basetypes/JobUsageRecord.java
+++ b/src/main/java/org/gcube/accounting/datamodel/basetypes/JobUsageRecord.java
@@ -172,12 +172,14 @@ public abstract class JobUsageRecord extends BasicUsageRecord {
 		}
 	}
 	
-	public long getWallDuration() {
+	public long getWallDuration() throws InvalidValueException {
 		Long wallDuration = (Long) this.resourceProperties.get(WALL_DURATION);
 		if(wallDuration == null){
 			try {
 				wallDuration = calculateWallDuration();
-			} catch(Exception e){}
+			} catch(InvalidValueException e){
+				throw e;
+			}
 		}
 		return wallDuration;
 	}