diff --git a/lib/private/Collaboration/Collaborators/MailPlugin.php b/lib/private/Collaboration/Collaborators/MailPlugin.php
index 8c2efce6f0d3b..d34d9fb0087a6 100644
--- a/lib/private/Collaboration/Collaborators/MailPlugin.php
+++ b/lib/private/Collaboration/Collaborators/MailPlugin.php
@@ -165,8 +165,8 @@ public function search($search, $limit, $offset, ISearchResult $searchResult) {
 							if (!$this->isCurrentUser($cloud) && !$searchResult->hasResult($userType, $cloud->getUser())) {
 								$singleResult = [[
 									'label' => $displayName,
-									'uuid' => $contact['UID'],
-									'name' => $contact['FN'],
+									'uuid' => $contact['UID'] ?? $emailAddress,
+									'name' => $contact['FN'] ?? $displayName,
 									'value' => [
 										'shareType' => IShare::TYPE_USER,
 										'shareWith' => $cloud->getUser(),
@@ -205,8 +205,8 @@ public function search($search, $limit, $offset, ISearchResult $searchResult) {
 							if ($addToWide && !$this->isCurrentUser($cloud) && !$searchResult->hasResult($userType, $cloud->getUser())) {
 								$userResults['wide'][] = [
 									'label' => $displayName,
-									'uuid' => $contact['UID'],
-									'name' => $contact['FN'],
+									'uuid' => $contact['UID'] ?? $emailAddress,
+									'name' => $contact['FN'] ?? $displayName,
 									'value' => [
 										'shareType' => IShare::TYPE_USER,
 										'shareWith' => $cloud->getUser(),
@@ -226,8 +226,8 @@ public function search($search, $limit, $offset, ISearchResult $searchResult) {
 						}
 						$result['exact'][] = [
 							'label' => $displayName,
-							'uuid' => $contact['UID'],
-							'name' => $contact['FN'],
+							'uuid' => $contact['UID'] ?? $emailAddress,
+							'name' => $contact['FN'] ?? $displayName,
 							'type' => $emailAddressType ?? '',
 							'value' => [
 								'shareType' => IShare::TYPE_EMAIL,
@@ -237,8 +237,8 @@ public function search($search, $limit, $offset, ISearchResult $searchResult) {
 					} else {
 						$result['wide'][] = [
 							'label' => $displayName,
-							'uuid' => $contact['UID'],
-							'name' => $contact['FN'],
+							'uuid' => $contact['UID'] ?? $emailAddress,
+							'name' => $contact['FN'] ?? $displayName,
 							'type' => $emailAddressType ?? '',
 							'value' => [
 								'shareType' => IShare::TYPE_EMAIL,