diff --git a/backend/src/uxbox/tasks.clj b/backend/src/uxbox/tasks.clj
index ea25a1ce4..c97ec8198 100644
--- a/backend/src/uxbox/tasks.clj
+++ b/backend/src/uxbox/tasks.clj
@@ -51,7 +51,7 @@
   [{:id "every 1 hour"
     :cron #uxbox/cron "1 1 */1 * * ? *"
     :fn #'uxbox.tasks.demo-gc/handler
-    :props {:foo "bar"}}])
+    :props {:foo 1}}])
 
 (defstate scheduler
   :start (as-> (impl/scheduler-verticle {:schedule schedule}) $$
diff --git a/backend/src/uxbox/tasks/demo_gc.clj b/backend/src/uxbox/tasks/demo_gc.clj
index d40e990b9..3d3948e73 100644
--- a/backend/src/uxbox/tasks/demo_gc.clj
+++ b/backend/src/uxbox/tasks/demo_gc.clj
@@ -16,5 +16,8 @@
 (defn handler
   {:uxbox.tasks/name "demo-gc"}
   [{:keys [props] :as task}]
-  (Thread/sleep 500)
-  (prn (.getName (Thread/currentThread)) "demo-gc" (:id task) (:props task)))
+  (try
+    (Thread/sleep 100)
+    (prn (.getName (Thread/currentThread)) "demo-gc" (:id task) (:props task))
+    (catch Throwable e
+      nil)))
diff --git a/backend/src/uxbox/tasks/impl.clj b/backend/src/uxbox/tasks/impl.clj
index 9de5eec2b..d9f1d452f 100644
--- a/backend/src/uxbox/tasks/impl.clj
+++ b/backend/src/uxbox/tasks/impl.clj
@@ -180,14 +180,11 @@
   (db/with-atomic [conn db/pool]
     (-> (db/query-one conn [sql:lock-scheduled-task id])
         (p/then (fn [result]
-                  (if result
-                    (do
-                      (prn (thr-name) "execute-scheduled-task" "task-locked")
-                      (-> (p/do! ((:fn stask) stask))
-                          (p/catch (fn [e]
-                                     (log/warn "Excepton happens on executing scheduled task" e)
-                                     nil))))
-                    (prn (thr-name) "execute-scheduled-task" "task-already-locked"))))
+                  (when result
+                    (-> (p/do! ((:fn stask) stask))
+                        (p/catch (fn [e]
+                                   (log/warn "Excepton happens on executing scheduled task" e)
+                                   nil))))))
         (p/finally (fn [v e]
                      (-> (vc/current-context)
                          (schedule-task stask)))))))
@@ -196,14 +193,13 @@
   [cron]
   (s/assert tm/cron? cron)
   (let [^Instant now (tm/now)
-        ^Instant next (.toInstant (.getNextValidTimeAfter cron (Date/from now)))
+        ^Instant next (tm/next-valid-instant-from cron now)
         ^Duration duration (Duration/between now next)]
     (.toMillis duration)))
 
 (defn- schedule-task
   [ctx {:keys [cron] :as stask}]
   (let [ms (ms-until-valid cron)]
-    (prn (thr-name) "schedule-task" (:id stask) ms)
     (vt/schedule! ctx (assoc stask
                              :ctx ctx
                              ::vt/once true