diff --git a/src/main/java/org/gcube/infrastructure/detachedres/detachedreslibrary/server/is/DetachedREsBuilder.java b/src/main/java/org/gcube/infrastructure/detachedres/detachedreslibrary/server/is/DetachedREsBuilder.java
index 53fd0bb..22789d9 100644
--- a/src/main/java/org/gcube/infrastructure/detachedres/detachedreslibrary/server/is/DetachedREsBuilder.java
+++ b/src/main/java/org/gcube/infrastructure/detachedres/detachedreslibrary/server/is/DetachedREsBuilder.java
@@ -57,19 +57,25 @@ public class DetachedREsBuilder {
 					for (GatewayJAXB gatewayJAXB : gatewaysJAXB) {
 						Gateway gateway = new Gateway(gatewayJAXB.getScope(), gatewayJAXB.getName(),
 								gatewayJAXB.getDescription());
-						try {
-							String startDate = dateFormat.format(gatewayJAXB.getStartDate());
-							gateway.setStartDate(startDate);
-						} catch (Exception e) {
-							logger.error("Invalid start date format for gateway: " + gatewayJAXB.getName());
+
+						if (gatewayJAXB.getStartDate() != null) {
+
+							try {
+								String startDate = dateFormat.format(gatewayJAXB.getStartDate());
+								gateway.setStartDate(startDate);
+							} catch (Exception e) {
+								logger.error("Invalid start date format for gateway: " + gatewayJAXB.getName());
+							}
 						}
 
-						try {
-							String endDate = dateFormat.format(gatewayJAXB.getEndDate());
-							gateway.setEndDate(endDate);
-						} catch (Exception e) {
-							logger.error("Invalid end date format for gateway: " + gatewayJAXB.getName());
+						if (gatewayJAXB.getEndDate() != null) {
+							try {
+								String endDate = dateFormat.format(gatewayJAXB.getEndDate());
+								gateway.setEndDate(endDate);
+							} catch (Exception e) {
+								logger.error("Invalid end date format for gateway: " + gatewayJAXB.getName());
 
+							}
 						}
 						gateway.setCatalogUrl(gatewayJAXB.getCatalogUrl());
 
@@ -120,19 +126,24 @@ public class DetachedREsBuilder {
 			ArrayList<VO> vos = new ArrayList<>();
 			for (VOJAXB voJAXB : gatewayJAXB.getVos()) {
 				VO vo = new VO(voJAXB.getScope(), voJAXB.getName(), voJAXB.getDescription());
-				try {
-					String startDate = dateFormat.format(voJAXB.getStartDate());
-					vo.setStartDate(startDate);
-				} catch (Exception e) {
-					logger.error("Invalid start date format for VO: " + voJAXB.getName());
+
+				if (voJAXB.getStartDate() != null) {
+					try {
+						String startDate = dateFormat.format(voJAXB.getStartDate());
+						vo.setStartDate(startDate);
+					} catch (Exception e) {
+						logger.error("Invalid start date format for VO: " + voJAXB.getName());
+					}
 				}
 
-				try {
-					String endDate = dateFormat.format(voJAXB.getEndDate());
-					vo.setEndDate(endDate);
-				} catch (Exception e) {
-					logger.error("Invalid end date format for VO: " + voJAXB.getName());
+				if (voJAXB.getEndDate() != null) {
+					try {
+						String endDate = dateFormat.format(voJAXB.getEndDate());
+						vo.setEndDate(endDate);
+					} catch (Exception e) {
+						logger.error("Invalid end date format for VO: " + voJAXB.getName());
 
+					}
 				}
 				vo.setCatalogUrl(voJAXB.getCatalogUrl());
 
@@ -159,19 +170,24 @@ public class DetachedREsBuilder {
 			ArrayList<VRE> vres = new ArrayList<>();
 			for (VREJAXB vreJAXB : voJAXB.getVres()) {
 				VRE vre = new VRE(vreJAXB.getScope(), vreJAXB.getName(), vreJAXB.getDescription());
-				try {
-					String startDate = dateFormat.format(vreJAXB.getStartDate());
-					vre.setStartDate(startDate);
-				} catch (Exception e) {
-					logger.error("Invalid start date format for VO: " + vreJAXB.getName());
+
+				if (vreJAXB.getStartDate() != null) {
+					try {
+						String startDate = dateFormat.format(vreJAXB.getStartDate());
+						vre.setStartDate(startDate);
+					} catch (Exception e) {
+						logger.error("Invalid start date format for VO: " + vreJAXB.getName());
+					}
 				}
 
-				try {
-					String endDate = dateFormat.format(vreJAXB.getEndDate());
-					vre.setEndDate(endDate);
-				} catch (Exception e) {
-					logger.error("Invalid end date format for VO: " + vreJAXB.getName());
+				if (vreJAXB.getEndDate() != null) {
+					try {
+						String endDate = dateFormat.format(vreJAXB.getEndDate());
+						vre.setEndDate(endDate);
+					} catch (Exception e) {
+						logger.error("Invalid end date format for VO: " + vreJAXB.getName());
 
+					}
 				}
 				vre.setCatalogUrl(vreJAXB.getCatalogUrl());
 				vre.setManagers(vreJAXB.getManagers());