S3 Events to SQS Trigger - Unable to validate the following destination configuration

I am trying to trigger SQS Events when an Object is created/Put in S3 Bucket. I followed everything mentioned here to the letter. Yet, I am getting the error message from Cloudformation :-

Unable to validate the following destination configurations. (Service:S3, Status Code: 400, Reqeust Id: xxxx....)

I have the following bucket policies :-

Deny Non SSL requests :-

Effect:"Deny"
Action: s3: *
Condition :{
    "Bool": {
          "aws:SecureTransport":"false"
     }
}

Deny POST or pre-signed URL requests

Effect :"Deny"
NotAction: "s3:InitiateReplication"
Condition:{
  "StringNotEquals":{
       "s3:authType": "REST-HEADER"

1. First, I deployed S3 Stack without Event Trigger
2. Then, I deployed KMS stack with S3 policy
3. Then, I deployed SQS Stack with policy and used the above KMS for encryption
4. Then, I updated S3 stack to enable Event trigger for all Object Created

I am getting Unable to validate the following destination configurations. (Service:S3, Status Code: 400, Reqeust Id: xxxx....)

Please help, if I am missing something !!