diff --git a/app/controllers/resources/room_request.php b/app/controllers/resources/room_request.php
index 26a0a8a17e26300ff536eae8b197fc01fbdc9d8d..2b25b7f9d6efb1f512cfb0e2aa6b8878a5595c16 100644
--- a/app/controllers/resources/room_request.php
+++ b/app/controllers/resources/room_request.php
@@ -1478,6 +1478,35 @@ class Resources_RoomRequestController extends AuthenticatedController
                 $this->alternative_rooms = array_merge($this->alternative_rooms, $request_rooms);
             }
         }
+
+        // add all booked rooms as well
+        $booked_rooms = [];
+        foreach($this->request_time_intervals as $key => $data) {
+            foreach ($data['intervals'] as $timeslot) {
+                if (!isset($booked_rooms[$timeslot['booked_room']])) {
+                    $room = Room::find($timeslot['booked_room']);
+                    if ($room) {
+                        $booked_rooms[$timeslot['booked_room']] = $room;
+                    }
+                }
+            }
+        }
+
+        if (!empty($booked_rooms)) {
+            $this->alternative_rooms = array_merge($booked_rooms, $this->alternative_rooms);
+        }
+
+        // deduplicate array
+        $deduplicated = [];
+
+        foreach ($this->alternative_rooms as $room) {
+            if (!isset($deduplicated[$room->id])) {
+                $deduplicated[$room->id] = $room;
+            }
+        }
+
+        $this->alternative_rooms = $deduplicated;
+
         foreach ($this->alternative_rooms as $room) {
             $this->metadate_available[$room->id] = [];
             $this->room_availability[$room->id] = [];
diff --git a/lib/models/resources/ResourceRequest.class.php b/lib/models/resources/ResourceRequest.class.php
index 67b3b982176dec3ae0111ca0769bb892697a370a..d7435c8cde8129e3b9f40935b4b5b9ea47a68241 100644
--- a/lib/models/resources/ResourceRequest.class.php
+++ b/lib/models/resources/ResourceRequest.class.php
@@ -1356,7 +1356,6 @@ class ResourceRequest extends SimpleORMap implements PrivacyObject, Studip\Calen
         } elseif ($this->course_id) {
             $course = new Seminar($this->course_id);
             if ($course) {
-                $strings[] = 'ct';
                 $strings[] = $course->getDatesTemplate('dates/seminar_html_roomplanning',
                     [
                         'shrink'    => false,
diff --git a/templates/dates/seminar_html_roomplanning.php b/templates/dates/seminar_html_roomplanning.php
index 97133e49584995d8b140a6e612ae97cd97cf5cce..f3311494aefeaa419cbf07d22f1a31756089e78f 100644
--- a/templates/dates/seminar_html_roomplanning.php
+++ b/templates/dates/seminar_html_roomplanning.php
@@ -27,7 +27,8 @@ if (!empty($dates['regular']['turnus_data']) || !empty($dates['irregular'])) :
             [
                 'assigned' => $cycle['assigned_rooms'],
                 'freetext' => $cycle['freetext_rooms'],
-                'plain'    => true]
+                'link'     => true
+            ]
         );
     endif;