I'm trying to connect to AWS DynamoDb by creating an AmazonDynamoDBClient.
I'm getting the following exception:

Amazon.Runtime.AmazonClientException: No RegionEndpoint or ServiceURL configured
at Amazon.Runtime.ClientConfig.Validate()
at Amazon.Runtime.AmazonServiceClient..ctor(AWSCredentials credentials, ClientConfig config)

I have the following lines in my App.Config file (the actual keys are in my code):

  <appSettings>
    <add key="AWSProfileName" value="development" />
    <add key="AWSAccessKey" value="XXXXXXXXXX" />
    <add key="AWSSecretKey" value="YYYYYYYYYY" />
    <add key="AWSRegion" value="us-east-2" />
  </appSettings>

I also have a credentials file under the AWS folder. Includes the following:

[development]
aws_access_key_id = XXXXXXXX
aws_secret_access_key = YYYYYYYYYY

In my code, I'm simply calling to:

AmazonDynamoDBClient client = new AmazonDynamoDBClient();

I'm working in visual-studio 2019. This used to work when I was working in a simple console application environment. Now I am working under Azure-Functions template project.
Why am I getting error?