Resque scheduled jobs are stuck in pending queue - ruby-on-rails

Question

I'm creating a DripEmail campaign for my app and using resque scheduler to schedule the tasks.
I've sceduled a static job, which runs every day at a specific time and collect the user's list based on the drip settings and sends out an emailer to them.
This is my resque job user_follow_up.rb
class UserFollowUp
#queue = :user_follow_up
def self.perform
User.each do |u|
# Send the emailers to only those who are not converted
if !user.is_converted and Date.today <= user.next_email
stage(u)
end
end
end
end
This is my scheduler.yml
UserFollowUp:
cron: "0 16 * * *"
I have 2 resque workers, one has my default set of tasks and the other for scheduler.
rake environment resque:work QUEUE=publish_story,accept_story,image_queue,Mango_mailer
and
rake environment resque:scheduler QUEUE=user_follow_up
When I open the resque admin interface, I'm able to see my static job detected in the list. I clicked the Queue Now button to test it. It properly enqueues the task to the queue, but doesn't execute. It keeps these tasks in the pending queue forever.
This is my resque.rake, it's required
require 'resque/tasks'
require 'resque/scheduler/tasks'
require 'resque/scheduler/server'
require 'active_record'
require 'mongoid'
require 'action_controller/railtie'
require 'active_support/buffered_logger'
# load the Rails app all the time
namespace :resque do
puts 'Loading Rails environment for Resque'
task :setup => :environment do
# The schedule doesn't need to be stored in a YAML, it just needs to
# be a hash. YAML is usually the easiest.
Resque.schedule = YAML.load_file("#{Rails.root}/config/scheduler.yml")
Resque::Scheduler.dynamic = true
Resque.logger.info 'Resque Scheduler Initialized!'
Resque.before_first_fork do
# Open the new separate log file
logfile = File.open(File.join(Rails.root, 'log', 'resque.log'), 'a')
# Activate file synchronization
logfile.sync = true
# Create a new buffered logger
Resque.logger = ActiveSupport::BufferedLogger.new(logfile)
Resque.logger.level = Logger::INFO
Resque.logger.info 'Resque Logger Initialized!'
puts 'Resque Logger Initialized!'
end
end
task 'resque:pool:setup' do
Resque::Pool.after_prefork do |job|
Resque.redis.client.reconnect
end
end
end
And this is my Gemfile
gem 'resque', github: 'resque/resque' , branch: '1-x-stable'
gem 'resque_mailer', github: 'zapnap/resque_mailer'
gem 'resque-scheduler'
I'm not sure what is the issue here. Please help me with this fix.