S3 Input Logstash, nothing shows up

I am new to aws s3.
-1, When i use CLI from KLAM, and run my config, nothing shows up.
-2, When i use the access and secret keys from KLAM, it has the error "Error: The AWS Access Key Id you provided does not exist in our records. ".

Below is my input portion of config file. Is there anything i shall do else? or install anything on my local machines?

input {
s3 {
access_key_id => "A*****************"
secret_access_key => "Zk**************************"
bucket => "aws-logs-035804961478-eu-west-1"
region => "eu-west-1"
prefix => "logs/"
codec => "gzip_lines"
type => "json"
sincedb_path => "/dev/null"
delete => false