I am trying to call a lambda function which will push some messages into the s3 bucket.But every time i am calling the lambda function i am getting the below error

 ClientError: An error occurred (AccessDenied) when calling the PutObject operation: Access Denied

Below is my lambda code

import json
import boto3

def lambda_handler(event, context):
s3 = boto3.client("s3")
#data = json.loads(event["Records"][0]["body"])
data = event["Records"][0]["body"]

s3.put_object(Bucket="sqsmybucket",Key="data.json", Body=json.dumps(data))
#print(event) 
return {
    'statusCode': 200,
    'body': json.dumps('Hello from Lambda!')     
}

I am using a user account which also has the role to access the S3

I have checked the s3 bucket permission and all public access are open for it

But i am repeatedly getting below error message in cloudwatch log

2020-06-05T23:48:20.920+05:30

[ERROR] ClientError: An error occurred (AccessDenied) when calling the PutObject operation: Access Denied
Traceback (most recent call last):
 File "/var/task/lambda_function.py", line 9, in lambda_handler
  s3.put_object(Bucket="sqsmybucket",Key="data.json", Body=json.dumps(data))
 File "/var/runtime/botocore/client.py", line 316, in _api_call
 return self._make_api_call(operation_name, kwargs)
 File "/var/runtime/botocore/client.py", line 626, in _make_api_call
  raise error_class(parsed_response, operation_name)

Please help i am really clueless about the situation.Thanks in advance.