Fixed document issue in communication

src/main/java/net/gepafin/tendermanagement/dao/DocumentDao.java

@@ -99,6 +99,8 @@ public class DocumentDao {
 		log.info("Uploading files userId={}, sourceType={}, fileType={}", userId,sourceType,fileType);
 		List<DocumentEntity> documentEntities = new ArrayList<>();
 		Long source = resolveSourceId(sourceId, sourceType);
+
+		if(files!=null) {
 			for (MultipartFile file : files) {
 				log.info("Uploading file '{}'", file.getOriginalFilename());
 				UploadFileOnAmazonS3Response uploadFileOnAmazonS3Response = uploadFileOnAmazonS3(file, sourceType, sourceId);
@@ -114,6 +116,7 @@ public class DocumentDao {
 					documentEntities.add(documentEntity);
 				}
 			}
+		}
 		documentRepository.saveAll(documentEntities);
 
 		/** This code is responsible for adding a version history log for the "Upload call or application document based on source type" operation. **/