Don't send more pm's after a user has been blocked from making posts. This can happen if a staff member flags posts that are already hidden.

app/services/spam_rules_enforcer.rb

@@ -48,8 +48,9 @@ class SpamRulesEnforcer
 
   def punish_user
     Post.transaction do
-      UserBlocker.block(@user, nil, {message: :too_many_spam_flags})
-      GroupMessage.create(Group[:moderators].name, :user_automatically_blocked, {user: @user, limit_once_per: false})
+      if UserBlocker.block(@user, nil, {message: :too_many_spam_flags})
+        GroupMessage.create(Group[:moderators].name, :user_automatically_blocked, {user: @user, limit_once_per: false})
+      end
     end
   end
 

app/services/user_blocker.rb

@@ -14,9 +14,13 @@ class UserBlocker
 
   def block
     hide_posts
-    @user.blocked = true
-    if @user.save
-      SystemMessage.create(@user, @opts[:message] || :blocked_by_staff)
+    unless @user.blocked?
+      @user.blocked = true
+      if @user.save
+        SystemMessage.create(@user, @opts[:message] || :blocked_by_staff)
+      end
+    else
+      false
     end
   end