diff --git a/dhp-workflows/dhp-graph-mapper/src/main/java/eu/dnetlib/dhp/oa/graph/raw/MigrateHdfsMdstoresApplication.java b/dhp-workflows/dhp-graph-mapper/src/main/java/eu/dnetlib/dhp/oa/graph/raw/MigrateHdfsMdstoresApplication.java
index ab6f54b92..f1f59b398 100644
--- a/dhp-workflows/dhp-graph-mapper/src/main/java/eu/dnetlib/dhp/oa/graph/raw/MigrateHdfsMdstoresApplication.java
+++ b/dhp-workflows/dhp-graph-mapper/src/main/java/eu/dnetlib/dhp/oa/graph/raw/MigrateHdfsMdstoresApplication.java
@@ -6,11 +6,7 @@ import static eu.dnetlib.dhp.common.SparkSessionSupport.runWithSparkSession;
 import java.io.IOException;
 import java.io.StringReader;
 import java.text.SimpleDateFormat;
-import java.util.Arrays;
-import java.util.Date;
-import java.util.Optional;
-import java.util.Set;
-import java.util.UUID;
+import java.util.*;
 import java.util.stream.Collectors;
 
 import org.apache.commons.io.IOUtils;
@@ -24,6 +20,7 @@ import org.apache.http.impl.client.CloseableHttpClient;
 import org.apache.http.impl.client.HttpClients;
 import org.apache.spark.SparkConf;
 import org.apache.spark.api.java.JavaSparkContext;
+import org.apache.spark.api.java.function.FilterFunction;
 import org.apache.spark.api.java.function.MapFunction;
 import org.apache.spark.sql.Encoders;
 import org.apache.spark.sql.Row;
@@ -110,6 +107,7 @@ public class MigrateHdfsMdstoresApplication extends AbstractMigrationApplication
 				.read()
 				.parquet(validPaths)
 				.map((MapFunction<Row, String>) MigrateHdfsMdstoresApplication::enrichRecord, Encoders.STRING())
+				.filter((FilterFunction<String>) Objects::nonNull)
 				.toJavaRDD()
 				.mapToPair(xml -> new Tuple2<>(new Text(UUID.randomUUID() + ":" + type), new Text(xml)))
 				// .coalesce(1)
@@ -135,13 +133,14 @@ public class MigrateHdfsMdstoresApplication extends AbstractMigrationApplication
 			reader.setFeature("http://apache.org/xml/features/disallow-doctype-decl", true);
 			final Document doc = reader.read(new StringReader(xml));
 			final Element head = (Element) doc.selectSingleNode("//*[local-name() = 'header']");
+
 			head.addElement(new QName("objIdentifier", DRI_NS_PREFIX)).addText(r.getAs("id"));
 			head.addElement(new QName("dateOfCollection", DRI_NS_PREFIX)).addText(collDate);
 			head.addElement(new QName("dateOfTransformation", DRI_NS_PREFIX)).addText(tranDate);
 			return doc.asXML();
 		} catch (final Exception e) {
 			log.error("Error patching record: " + xml);
-			throw new RuntimeException("Error patching record: " + xml, e);
+			return null;
 		}
 	}