fix error on reactions

app/carousels/guild.rb

@@ -40,10 +40,12 @@ class GuildCarousel < Carousel
       end
 
     # Remove reaction
-    event.message.reacted_with(reaction).each do |r|
-      event.message.delete_reaction(r.id, reaction) unless r.current_bot?
+    if reaction
+      event.message.reacted_with(reaction).each do |r|
+        event.message.delete_reaction(r.id, reaction) unless r.current_bot?
+      end
     end
 
-    BotResponse.new(carousel: carousel, embed: embed)
+    BotResponse.new(carousel: carousel, embed: embed) if embed
   end
 end

app/models/bot_response.rb

@@ -48,8 +48,6 @@ class BotResponse
       )
     when Array
       Carousel.create(message_id: message.id, options: @carousel)
-    when nil
-      Carousel.create(message_id: message.id)
     end
 
     # React

bot.rb

@@ -149,7 +149,7 @@ bot.reaction_add do |event|
 
   if reply
     BotController.reply(bot, event, reply)
-  elsif event.message.reactions[Emoji::CROSS].count
+  elsif event.message.reactions[Emoji::CROSS]&.count
     crosses = event.message.reacted_with(Emoji::CROSS)
     crosses.each do |cross|
       member = event.server.member(cross.id)