If this error appears

NullReferenceException: Object reference not set to an instance of an object Amazon.AWSConfigs.GetSection

We need to modify the awsconfig.xml to this:

<?xml version="1.0" encoding="utf-8"?>
<aws correctForClockSkew="true" region="ap-southeast-2">
    <logging logTo="UnityLogger"
             logResponses="Always"
             logMetrics="true"
             logMetricsFormat="JSON" />
	<s3 useSignatureVersion4="true" /> 
</aws>

correctForClockSkew should fix it