diff --git a/lib/Controller/WorkspaceController.php b/lib/Controller/WorkspaceController.php
index 055e0ef9..f92d2946 100644
--- a/lib/Controller/WorkspaceController.php
+++ b/lib/Controller/WorkspaceController.php
@@ -96,8 +96,8 @@ public function createWorkspace(string $spaceName,
 			throw new BadRequestException('spaceName must be provided');
 		}
 
-		if($this->workspaceCheck->containSpecialChar($spaceName)) {
-			throw new BadRequestException('Your Workspace name must not contain the following characters: ' . implode(" ", str_split(WorkspaceCheckService::CHARACTERS_SPECIAL)));
+		if ($this->workspaceCheck->containSpecialChar($spaceName)) {
+			throw new BadRequestException('Your Workspace name must not contain the following characters: ' . implode(' ', str_split(WorkspaceCheckService::CHARACTERS_SPECIAL)));
 		}
 		
 		if ($this->workspaceCheck->isExist($spaceName)) {
@@ -196,8 +196,24 @@ public function findAll(): JSONResponse {
 			) : $workspace;
 
 			$gids = array_keys($space['groups'] ?? []);
-			$groups = array_map(fn ($gid) => $this->groupManager->get($gid), $gids);
-	
+
+			$groups = [];
+
+			foreach ($gids as $gid) {
+				$group = $this->groupManager->get($gid);
+
+				if (is_null($group)) {
+					$this->logger->warning(
+						"Be careful, the $gid group is not exist in the oc_groups table."
+						. " But, it's present in the oc_group_folders_groups table."
+						.  'It necessary to recreate it with the occ command.'
+					);
+					continue;
+				}
+
+				$groups[] = $group;
+			}
+
 			$space['groups'] = GroupFormatter::formatGroups($groups);
 			$space['users'] = $this->workspaceService->addUsersInfo($space);
 	
@@ -304,7 +320,7 @@ public function renameSpace(array|string $workspace,
 		}
 
 		if ($this->workspaceCheck->containSpecialChar($newSpaceName)) {
-			throw new BadRequestException('Your Workspace name must not contain the following characters: ' . implode(" ", str_split(WorkspaceCheckService::CHARACTERS_SPECIAL)));
+			throw new BadRequestException('Your Workspace name must not contain the following characters: ' . implode(' ', str_split(WorkspaceCheckService::CHARACTERS_SPECIAL)));
 		}
 
 		if ($newSpaceName === false ||