diff --git a/app/jobs/regular/delete_replies.rb b/app/jobs/regular/delete_replies.rb
index b8228c7a047..bbc0bec8ff4 100644
--- a/app/jobs/regular/delete_replies.rb
+++ b/app/jobs/regular/delete_replies.rb
@@ -22,7 +22,7 @@ module Jobs
         PostDestroyer.new(topic_timer.user, post, context: I18n.t("topic_statuses.auto_deleted_by_timer")).destroy
       end
 
-      topic_timer.execute_at = (replies.minimum(:created_at) || Time.zone.now) + topic_timer.duration.days.ago
+      topic_timer.execute_at = (replies.minimum(:created_at) || Time.zone.now) + topic_timer.duration.days
       topic_timer.save
     end
 
diff --git a/spec/jobs/delete_replies_spec.rb b/spec/jobs/delete_replies_spec.rb
new file mode 100644
index 00000000000..a1968bc671e
--- /dev/null
+++ b/spec/jobs/delete_replies_spec.rb
@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+describe Jobs::DeleteReplies do
+  fab!(:admin) { Fabricate(:admin) }
+
+  fab!(:topic) { Fabricate(:topic) }
+  fab!(:topic_timer) do
+    Fabricate(:topic_timer, status_type: TopicTimer.types[:delete_replies], duration: 2, user: admin, topic: topic, execute_at: 2.days.from_now)
+  end
+
+  before do
+    3.times { create_post(topic: topic) }
+  end
+
+  it "can delete replies of a topic" do
+    freeze_time (2.days.from_now)
+
+    expect {
+      described_class.new.execute(topic_timer_id: topic_timer.id)
+    }.to change { topic.posts.count }.by(-2)
+
+    topic_timer.reload
+    expect(topic_timer.execute_at).to eq_time(2.day.from_now)
+  end
+end