Inspec - Control Source Code Error - 503 "Service Unavailable"

We have written inspec control using aws-sdk and ruby to validate the S3 bucket. We are running the inspec against us-east-1 region.

But getting Control source code error - 503 service not available.

Tried running the same code manually after the s3 bucket is provisioned, but its not working out in pipeline.

1) Control Source Code Error /apps/cloudbees-je/cloudbees-data/workspace/xxxxx/security-compliance-profile/controls/s3-controls.rb:37 
     Failure/Error: its(location) { fail e.message } # rubocop: disable Style/SignalException

     RuntimeError:
       503 "Service Unavailable"
     # /usr/local/ruby_2.5.1/lib/ruby/gems/2.5.0/gems/inspec-2.1.72/lib/inspec/rule.rb:62:in `block (2 levels) in initialize'
     # /usr/local/ruby_2.5.1/lib/ruby/gems/2.5.0/gems/rspec-core-3.8.0/lib/rspec/core/example.rb:254:in `instance_exec'

Any help would be appreciated in knowing the cause regarding error - 503

The issue was the region against inspec running was not getting populated properly in Jenkins - groovy script.