diff --git a/lib/User/Backend.php b/lib/User/Backend.php
index e06aee48..87d392b4 100644
--- a/lib/User/Backend.php
+++ b/lib/User/Backend.php
@@ -37,7 +37,6 @@
 use OCP\IURLGenerator;
 use OCP\IUser;
 use OCP\IUserManager;
-use OCP\IUserSession;
 use OCP\Server;
 use OCP\User\Backend\ABackend;
 use OCP\User\Backend\ICountUsersBackend;
@@ -369,12 +368,10 @@ public function getCurrentUserId(): string {
 							}
 
 							$this->session->set('last-password-confirm', $this->timeFactory->getTime() + 4 * 365 * 24 * 3600);
-							$this->setSessionUser($userId);
 							return $userId;
 						} elseif ($this->userExists($tokenUserId)) {
 							$this->checkFirstLogin($tokenUserId);
 							$this->session->set('last-password-confirm', $this->timeFactory->getTime() + 4 * 365 * 24 * 3600);
-							$this->setSessionUser($tokenUserId);
 							return $tokenUserId;
 						} else {
 							// check if the user exists locally
@@ -396,7 +393,6 @@ public function getCurrentUserId(): string {
 							}
 							$this->checkFirstLogin($tokenUserId);
 							$this->session->set('last-password-confirm', $this->timeFactory->getTime() + 4 * 365 * 24 * 3600);
-							$this->setSessionUser($tokenUserId);
 							return $tokenUserId;
 						}
 					}
@@ -417,31 +413,6 @@ private function isAcceptableUserId(mixed $userId): bool {
 		return is_string($userId) && $userId !== '' && trim($userId) !== '';
 	}
 
-	/**
-	 * Set the user in IUserSession after bearer token validation.
-	 * Without this, DI-injected $userId is null in OCS controllers
-	 * and CalDAV plugins, causing 500 errors in Deck, Talk, and Tasks.
-	 *
-	 * Note: IUserSession is resolved via Server::get() rather than constructor
-	 * injection to avoid a circular dependency (IUserSession depends on this Backend).
-	 */
-	private function setSessionUser(string $userId): void {
-		try {
-			$userSession = Server::get(IUserSession::class);
-			$currentUser = $userSession->getUser();
-
-			// Only fetch and set if the session doesn't already have this user
-			if ($currentUser === null || $currentUser->getUID() !== $userId) {
-				$user = $this->userManager->get($userId);
-				if ($user !== null) {
-					$userSession->setUser($user);
-				}
-			}
-		} catch (\Throwable $e) {
-			$this->logger->debug('Failed to set session user after bearer validation: ' . $e->getMessage());
-		}
-	}
-
 	/**
 	 *
 	 * Performs first-login initialisation (home folder setup, skeleton copy, events)