Hi Manuel.
May be you bucket policy dont allow bucket operations.
Open your AWS web console, in S3 services, look for your bucket, and check at the bucket policy.
The key data it that you must allow all s3 operations with "Action":"s3:*", an you must list as "Resource" the content of your bucket and the bucket itself.

here it is a sample:
{
"Sid": "A_TEXT",
"Effect": "Allow",
"Principal": {
"AWS": "arn:aws:iam::332821161564:user/YOUR_AIM_USER"
},
"Action": "s3:*",
"Resource": ["arn:aws:s3:::YOUR_BUCKET/*","arn:aws:s3:::YOUR_BUCKET"]
}

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